· Space Systems Space Technologies Product Catalog ©2020 Sierra Nevada Corporation 3 1722 Boxelder Street • Louisville, CO 80027 USA • 303-530-1925 sncorp.com

Space Systems

Space Technologies Product Catalog

©2020 Sierra Nevada Corporation 2

1722 Boxelder Street • Louisville, CO 80027 USA • 303-530-1925

sncorp.com/spacecatalog • Email: [email protected]

Sierra Nevada Corporation’s Space Systems


Space Systems





Table of Contents

Space Technologies Product Catalog .......................................................................................................................................... 2

Table of Contents .................................................................................................................................................................. 3

Introduction ........................................................................................................................................................................... 6

Deployable Systems .................................................................................................................................................................. 11

Articulating Booms .............................................................................................................................................................. 12

Jackscrew Deployed Boom ................................................................................................................................................. 13

K-truss Boom ...................................................................................................................................................................... 15

Docking and Berthing Systems .................................................................................................................................................. 16

Passive Common Berthing Mechanism (PCBM) ................................................................................................................. 17

Electrical Power Systems ........................................................................................................................................................... 19

Cell Shorting Device Battery Switch .................................................................................................................................... 20

Cubesat Solar Array System—13 W Surface Mount Technology ....................................................................................... 22

Microsat Articulated Solar Array System— 400 W Articulated Array .................................................................................. 24

Microsat Rigid Panel Solar Array System—250 W Deployable Array ................................................................................. 26

Smallsat Solar Array System—780 W Articulated Array ..................................................................................................... 28

Flight Control Systems (FCS) and Thrust Vector Control (TVC) Systems ................................................................................. 30

Flight Control (FCS) and Thrust Vector Control Systems (TVC) ......................................................................................... 31

High Output Paraffin Actuators and Mechanisms ...................................................................................................................... 33

EH-3525 High Output Paraffin (HOP) Actuator ................................................................................................................... 34

IH-5055/-10055 High Output Paraffin (HOP) Actuators ...................................................................................................... 36

PP-35055 Resettable High-Force Pin Puller ....................................................................................................................... 38

PP-5501 Two-Position Latching Actuator ........................................................................................................................... 40

RO-9015 Two-Position Rotary Latching Actuator ............................................................................................................... 42

SP-5025 High Output Paraffin (HOP) Pin Puller ................................................................................................................. 44

SP-5085 High Output Paraffin (HOP) Pin Puller ................................................................................................................. 46

Instrument Door and Cover Systems ......................................................................................................................................... 48

Instrument Door and Cover Systems .................................................................................................................................. 49

Launch Adapters and Separation Systems ................................................................................................................................ 51

Fast-Acting Shockless Separation Nut (FASSN) 30K ......................................................................................................... 52

Hold Down Release Mechanism (HDRM) ........................................................................................................................... 54

Low Shock Release Mechanism (LSRM) 5K ...................................................................................................................... 56

Microsat Deployment Module .............................................................................................................................................. 58

Space Systems





QwkSep® 15 Low-Profile Separation System (LPSS) ......................................................................................................... 60

QwkSep® 24 Low-Profile Separation System (LPSS) ......................................................................................................... 62

Pointing Systems and Motion Control ........................................................................................................................................ 64

C14 Bi-Axis Gimbal ............................................................................................................................................................. 66

C14 Incremental Rotary Actuator ........................................................................................................................................ 68

C14–750 W Solar Array Drive Assembly ............................................................................................................................ 70



CEH25 Compact Incremental Rotary Actuator, 3-Phase ................................................................................................... 76

DM45L Gearmotor .............................................................................................................................................................. 78

EH25 Bi-Axis Gimbal, 3-Phase ........................................................................................................................................... 80

EH25 Incremental Rotary Actuator, 3-Phase ...................................................................................................................... 82

Electronic Control Unit (ECU) ............................................................................................................................................. 84

eMotor ................................................................................................................................................................................. 86

HT32 Gearmotor ................................................................................................................................................................. 88

HT45S Gearmotor with Brake ............................................................................................................................................. 90

H25 Bi-Axis Gimbal, 4-Phase .............................................................................................................................................. 92

LDC20 Low-Disturbance Gimbal ......................................................................................................................................... 94

Lightweight 2-Axis Mini Gimbal ........................................................................................................................................... 96

LT32 Gearmotor .................................................................................................................................................................. 98

LT45L Gearmotor .............................................................................................................................................................. 100

LT45S Gearmotor with Brake ............................................................................................................................................ 102

M45L Motor ....................................................................................................................................................................... 104

M45S Motor ...................................................................................................................................................................... 106

Rotary Drive Electronics (RDE) ......................................................................................................................................... 108

Simple Stepper Driver (SSD) ............................................................................................................................................ 110

Size 23 Incremental Rotary Actuator ................................................................................................................................ 112

T25 Incremental Rotary Actuator (RA) .............................................................................................................................. 114

Universal Microstepping Control Driver (UMCD) ............................................................................................................... 116

Production and Test Capabilities .............................................................................................................................................. 118

Cable and Harnessing Capability ...................................................................................................................................... 119

Spacecraft Servicing Technologies .......................................................................................................................................... 121

Advanced Manipulator Technology for Spacecraft Servicing ............................................................................................ 122

Orbital Express Capture System ....................................................................................................................................... 123

Space Systems





Structural, Power and Data Port (SPDP) .......................................................................................................................... 125

Thermal Control Systems ......................................................................................................................................................... 127

Miniature Satellite Energy-Regulating Radiator (MiSER) .................................................................................................. 128

Passive Thermal Control Heat Switch ............................................................................................................................... 130

Passive Thermal Louvers .................................................................................................................................................. 132

Thin Plate Heat Switch ...................................................................................................................................................... 134

Acronym List ............................................................................................................................................................................ 136

Space Systems

Introduction




Introduction

Owned by Chairwoman and President Eren Ozmen and CEO Fatih Ozmen, SNC is a trusted leader in solving the world’s toughest challenges through best-of-breed, open architecture engineering in Space Systems, Commercial Solutions, and National Security and Defense. SNC is recognized among the three most innovative U.S. companies in space, as a Tier One Superior Supplier for the U.S. Air Force, and as one of America’s fastest growing companies. SNC’s 55-year legacy of state-of-the art civil, military and commercial solutions includes delivering more than 4,000 space systems, subsystems and components to customers worldwide, and participation in more than 450 missions to space, including Mars

About SNC’s Space Systems

SNC’s Space Systems consists of three primary business units that include 1) Space Exploration Systems (SES) 2) Spacecraft & Space Technologies (STS) 3) Orbital Technologies Corp (RBI). Space Systems is comprised of a talented workforce of industry experts who are developing efficient approaches to crew and cargo spaceflight transportation, satellites, propulsion systems, and spacecraft subsystems and components for U.S. Government, commercial, and international customers. SNC provides a complete, integrated package to its customers to satisfy the expanding demand for global, affordable, rapid access to space. To date, SNC’s products have successfully supported more than 450 space missions.

Space Systems’ Product Lines. SNC continues to invest in our systems and add to our global client list, including many major aerospace companies. Our product lines have grown dramatically as we further advance the commercialization of space.

Space Systems

Introduction




Space Technologies’ Expansive Exploration of Earth and our Planetary Solar System

With more than 25 years of space heritage, SNC’s Space Systems has concluded more than 70 programs for NASA and more than 50 other clients. It has participated in more than 450 successful space missions through the delivery of more than 4,000 systems, subsystems, and components. SNC’s spacecraft components and subsystems have been on multiple interplanetary missions including the actuators and motors that power the Mars Rovers, and our hybrid rocket technologies that powered the first commercial spaceplane to suborbital space.

SNC is changing how we use space by building innovative, reliable, and lower-cost space transportation vehicles and satellites like Dream Chaser® spacecraft, TacSat-2, Trailblazer, and STPSat-5. Other products span the spectrum, giving SNC an extensive and impressive role in supporting defense, civil, international, and commercial programs. We continue this long legacy of creating advanced space products such as avionics, solar arrays, and lightweight composite structures to benefit the spacecraft of the future.

Planetary Exploration. SNC has a significant presence in space with a long legacy of contribution to government, commercial, and civil customers on missions both near and far.

Space Systems

Introduction




Space Technologies Product Line

SNC’s Space Systems was formed as a business area in early 2009 through the consolidation of SpaceDev, Inc. (including SpaceDev’s subsidiary Starsys Research) and MicroSat Systems, Inc. SNC is an industry leader in precision space mechanisms and complex spacecraft subsystems with an unmatched heritage of products including thousands of devices successfully flown on hundreds of spacecraft. SNC’s Space Systems has rapidly become a supplier of choice by offering an expansive portfolio of space-qualified products and subsystems that includes:

Deployable Systems

Docking and Berthing Systems

Electrical Power Systems

Flight and Thrust Vector Control Systems

High Output Paraffin Actuators and Mechanisms

Instrument Door and Cover Systems

Launch Adapters and Separation Systems

Pointing Systems and Motion Control

Production and Test Capabilities

Thermal Control Systems

Facilities

SNC’s Space Systems’ primary facility is located in Louisville, Colorado. It has more than 230,000 square feet of office and manufacturing space that is dedicated to spaceflight subsystem and component assembly and test, small satellite end-to-end production, and fabrication of SNC’s Dream Chaser multi-mission space utility vehicle spacecraft. The facility features:

AS9100 certification

Precision temperature and humidity control

ISO 8 modular production floor

ISO 7 clean rooms

ISO 5 laminar flow benches

Specialized equipment and tools for the handling, cleaning, assembly, and cleanliness-verification of optical-grade products

End-to-end testing capabilities including vibration, shock, a rapid transition Thermal Test Chamber, radio frequency, thermal, thermal-vacuum and stiffness, as well as functional tests

Large Area Pulsed Solar Simulator for solar array testing

Space Technologies Product Line Capabilities

Louisville, Colorado ISO 8 Modular Production Floor

Louisville, Colorado Thermal and Vacuum Chambers

Space Systems

Introduction




At our Durham, North Carolina, location, SNC’s Space Systems employs a highly skilled team of experts who lead the aerospace industry in electromechanical motion control. The tenured team of engineers and technicians focus on the design, development, and production of spaceflight motors, actuators, and electromechanical devices with an unmatched, diverse product heritage. The Durham facility is located within minutes of the Raleigh-Durham International Airport and features:

AS9100 certification

ISO 8 modular production floor

ISO 7 clean rooms

ISO 5 laminar flow benches

End-to-end testing capabilities including vibration, thermal, thermal-vacuum, stiffness, motor/actuator speed-torque-accuracy, line of sight micro-motion jitter testing, and functional testing

The Durham and Louisville locations share personnel and facility resources to optimize program execution based on customer needs. Other facilities include a dedicated propulsion and environmental systems office located in Madison, Wisconsin, and local business development offices in Houston, Texas; Huntsville, Alabama; and Exploration Park, Florida.

Test Simulator Capabilities

SNC’s Space Systems Louisville location houses state-of-the-art production and test facilities, including the recently commissioned Large Area Pulsed Solar Simulator (LAPSS) that is used to verify solar array performance. The LAPSS, located in a large-scale testing zone, simulates the Sun to obtain accurate electrical performance measurements of solar panels.

SNC’s LAPSS is capable of measuring panels that are 3.5 m x 3.5 m square with the AM0 (air mass zero) spectrum at a rate of 10 pulses per minute. The industry-standard LAPSS equipment was purchased from Alpha Omega Power Technologies—a well-known supplier of solar simulators to the space industry. In addition, SNC verifies all of its solar array systems using supplementary industry measurement standards and equipment provided by solar cell manufacturers such as SolAero Technologies, SpectroLab, and Azur Space.

LAPSS Simulator. LAPSS is capable of obtaining accurate performance measurements.

LAPSS Test Area. An in-house LAPSS solar array test area for secondary verification processes.

Space Systems

Introduction




Engineering

SNC’s Space Systems boasts a highly skilled team of industry experts who focus on a broad range of technical specialties. The engineering group’s breadth and depth of experience sets SNC apart from the competition, allowing it to respond efficiently to customer needs—on production-type programs, as well as custom-engineered solutions. SNC’s talented personnel provide an array of engineering disciplines and tools summarized below:

Disciplines

Mechanical Engineering Electrical Engineering

Structural Engineering Systems Safety

Systems Engineering Manufacturing Engineering

Thermal Engineering Quality Assurance

Radio Frequency Engineering Structural Analysis

Guidance, Navigation, and Control Engineering Reliability Assurance

Thermal Analysis Finite Element Modeling

Tools

CAD AutoCAD SolidWorks Siemans NX

Structural Analysis MSC Nastran Nei Autodesk Nastran 2015 NX Nastran 8.5

NX CAE

Thermal Thermal Desktop SINDA G

Numerical Analysis MATLAB Simulink Mathcad

Electrical Simulations Pspice

Electrical Design OrCAD

Magnetic/Motor Analysis SPEED Infolytica MotorSolve Infolytica Magnet

Bearing Analysis Bearings 10+ Cobra AB Jones

Gear Analysis UTS Integrated Gear

Space Systems Deployable Systems

©2020 Sierra Nevada Corporation This Product is Export Controlled Under the Export Administration Regulations (EAR) 11



Deployable Systems

While many spacecraft are decreasing in size, physics will maintain the demand for large aperture subsystems. For that reason, SNC considers deployable structures to be a critical element in the future of microsatellite systems. Our Jackscrew boom system utilizes high-strength, high-stiffness articulated truss elements that ensure low-risk linear deployment. The structure and deployment system is readily integrated into mass- and volume-efficient super structures for planar arrays. Our K-truss booms are engineered with a strain-energy deployment system that reduces cost and is constructed with a nonconductive material that enables antenna integration.

Catalog data sheets for the SNC’s Space Systems Deployable Systems technology area include:

Articulating Booms

Jackscrew Deployed Boom

K-truss Boom

Space Systems Articulating Booms




Articulating Booms

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems deployable boom capabilities include articulating booms that use tube structures and hinges for accurate and repeatable deployment of payloads. Hinged deployed booms meet many mission needs where stability and system simplicity are critical. Articulated booms are often used to deploy optical systems, radiation or magnetometer instruments, and other stability-sensitive payloads. Cabling, wave guides, Multi-Layer Insulation (MLI), and other hardware can be firmly mounted along the length of the boom where an axially deployed boom could not be incorporated due to boom rotation or a risk of entanglement.

Articulated booms can use either a root/base stowed energy hinge or a motorized hinge to actuate the boom depending on mission requirements. Stowed energy hinges are simple, low-risk mechanisms that provide torsional force via redundant leaf springs while controlling the rate of deployment via integrated dampers. Stowed energy hinges are used on missions with a one-time boom deployment requirement and can include locking features if needed. SNC can also incorporate motors on the hinges to provide deployment torque for missions requiring more control of the boom to deploy multiple times or stop in multiple positions. Other features include:

180º hinges that can be incorporated along the length to increase the deployed-to-stowed expansion ratio as shown in the image above.

Integrated Hold Down Release Mechanisms to provide support during launch and mission operations prior to deployment.

SNC has significant experience and heritage in hinge-deployed booms and will collaborate with customers to determine the optimal solution for the required space mission.

Features

Gentle, smooth deployment Allows for attachment of equipment along the length of the boom

Excellent instrument stability and position accuracy Simple and redundant design provides low-risk deployment

Motor or stowed-energy driven deployment Highly tailorable for thermal stability, strength, and stiffness

High accuracy and stable

Applications

Optical systems and instruments Deployed radar antennas

Solar array deployment High-sensitivity instruments such as particle detectors and magnetometers

Articulated Boom. This deployed boom used a 90º base and 180º mid-length locking hinge to provide a 2:1 expansion ratio.

Space Systems Jackscrew Deployed Boom




Jackscrew Deployed Boom

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems Jackscrew Deployed Boom, shown at right under test, is a motor-deployed, high-stiffness and high-strength articulated truss. The jackscrew boom deploys in a purely linear/axial manner without the use of deployment canisters for de-spin as required for motorized coilable booms. Therefore, the jackscrew boom provides multiple payload or cabling attachment points along the length of the boom with a deadband-free, high mechanically advantaged deployment without the parasitic mass of a canister. The jackscrew drive system offers mass and volume efficiency improvements over canister-deployed booms.

The jackscrew boom deployment method also provides full structural integrity throughout deployment, thus allowing mid-deployment spacecraft maneuvering or other loading without the risk of collapsing the boom. The jackscrew boom can be re-stowed after deployment by reversal of the deployer motor.

The main components of the boom system, illustrated below, consist of the deployable boom assembly and the deployer assembly. The deployer assembly uses a system of redundant belts driven by an electric motor to synchronize and drive a series of jackscrews. The deployer also includes four structural tubes that position the stowed boom and enclose the jackscrew drive shafts, a detent at each corner of the deployer, and four foldable jackscrews.

Triangular cross-section booms are also available using three jackscrews. During deployment, the jackscrews (aka elevator screws) and deployment detent work together to sequentially expand and form each bay of the boom as it is deployed. At least one batten frame of the boom is engaged with the jackscrews at any point in time during deployment providing full structural integrity throughout deployment. The deployer jackscrews are restrained in their folded, stowed configuration during launch and prior to boom deployment. Following a signal to initiate deployment, the jackscrews are released and transition to their deployed, locked configuration. A brushless dc motor provides power to the system and limit switches identify first motion and successful deployment of the boom.

Jackscrew Deployed Boom Under Test

10-Bay Jackscrew Deployed Boom (stowed) Deployed Boom Cantilevered with 11-lb Tip Mass (no offloading)

Space Systems Jackscrew Deployed Boom




Features

Purely linear/axial deployment High-force deployment/retraction

Highly tailorable for thermal stability, strength, and stiffness Highly scalable and mass optimized

Simple, high-reliability, high-tension deployment Full stiffness and strength during deployment

Exposed payload interfaces throughout deployment and during pre-flight integration

Applications

Solar array and solar-sail deployment and retraction Instrument deployment and retraction

Antenna deployment/retraction Gravity gradient mass deployment and retraction

Synthetic Aperture Radar (SAR) deployment and retraction Spacecraft separation

Product Specifications for a 10-Bay Jackscrew Boom

Dimensions: 190-in long x 15.5-in diameter

1st Bending Mode: 6.9 Hz Tip Torsion Stiffness: 13,594 in-lb/rad

Mass: 11.7 lb 1st Torsion Mode: 16.4 Hz Tip Shear Stiffness: 25 lb/in

Space Systems K-truss Boom




K-truss Boom

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems K-truss Boom is an elastically deployed boom, which utilizes stowed energy for deployment. The K-truss boom deploys in a purely linear/axial manner unlike a conventional lanyard deployed coilable boom. Therefore the K-truss boom provides multiple payload or cabling attachment points to allow the deployment of objects along the length of the boom before, during, and after deployment.

This type of boom simplifies deployable structures on small satellites by eliminating the need for a drive motor and electronics. The resulting boom provides a nonrotating deployment with unprecedented thermal stability, precision, and repeatability, in addition to high stiffness and high strength. This type of deployed structure is also applicable to many spacecraft that have been traditionally limited to fiberglass coilable type booms. This enabling boom technology can increase satellite application capabilities, improve reliability, and reduce costs. The stowed and deployed K-truss boom is illustrated below.

Features

Exposed payload interfaces throughout deployment and during pre-flight integration

Nonconductive/magnetically “clean” materials available for integrated antennae or magnetometers

Highly tailorable for thermal stability, strength, and stiffness

Highly scalable and mass optimized

Predictable deployment behavior Zero deadband monolithic structure

Elastically deployed “tape” joints eliminate motorized actuation mass

Precision deployment and pointing accuracy of the payload

Applications

Solar array/solar-sail deployment Attitude control thrusters Gravity gradient mass deployment

Antenna deployment Instrument deployment Magnetometer deployment

Product Specifications*

Dimensions: 101.5-inch long x 9.5-inch diameter 1st Bending Mode: 3.5 Hz

System Mass: <15 lb Bending Stiffness: 1.14 lb/in

Stowed K-truss Boom Deployed K-truss Boom Section

K-truss Boom with Quadrifilar Helical Antenna Under Test

Space Systems Docking and Berthing Systems




Docking and Berthing Systems

Sierra Nevada Corporation (SNC) Space Systems solidified our docking and berthing technology by being a major subcontractor on the Orbital Express program, providing the system that captured and docked two spacecraft together on-orbit to allow for remote servicing such as refueling and replacement of outdated and expended components. We then leveraged this mechanical systems experience into becoming the go-to supplier for the industry standard Passive Common Berthing Mechanism (PCBM), required for spacecraft such as the Orbital Cygnus Advanced Maneuvering Vehicle and the Bigelow Expandable Activity Module (BEAM) to berth with the International Space Station (ISS).

Catalog data sheets for Sierra Nevada Corporation’s Docking and Berthing Systems technology area include:

Passive Common Berthing Mechanism (PCBM)

Space Systems Passive Common Berthing Mechanism





Design Description

Sierra Nevada Corporation’s (SNC) Space Systems has become the go-to supplier for the Passive Common Berthing Mechanism (PCBM), an industry standard mechanical and structural interface required to safely and reliably berth commercial or government spacecraft to the International Space Station (ISS).

SNC’s PCBM is a flight-proven system that allows alignment and environmental sealing between the ISS and pressurized vehicles. It is a fully passive assembly (active side permanently attached to the Space Station) with minimal moving parts.

SNC’s PCBM has been vetted and approved by NASA for compliance to the strict human-rating standards and pedigree that is required for International Space Station (ISS) applications. It has been fully tested to ensure compliance with functional performance and sealed interface requirements.

After delivery, SNC provides additional services to integrate the PCBM onto the vehicle and leak check the interface seals, as well as support NASA FE-1410 pressurized leak testing of the PCBM’s Active Common Berthing Mechanism (ACBM) interface.

Features

Fully tested and verified powered bolt nut assemblies (PNA), the main functional interface of the PCBM

Alignment pin socket assemblies provide fine alignment and take shear loads between the PCBM and ACBM

Thermal standoff assemblies maintain pre-load between the PCBM and the Active CBM (ACBM) on the ISS

Capture fittings provide an interface for the ACBM to grab and pull the PCBM to berth

Skirt segment assemblies shield the PCBM from micrometeoroid debris

Alignment guide assemblies provide gross alignment and clocking of the PCBM to the ACBM

Positive grounding paths to main PCBM structure

Applications

Berthing to the ISS for commercial or government customer missions

Heritage Programs

Orbital ATK Cygnus Cargo Resupply Service (CRS) Cygnus OA-4 - flown December 2015

Cygnus CRS Orb-1 and Orb-2 Cygnus CRS OA-5 through OA-8E flight systems delivered to customer

Cygnus CRS Orb-3 (vehicle lost during launch) Bigelow Expandable Activity Module (BEAM) flight system delivered to customer – launched April 2016

Northrop Grumman CRS Flight Launched April 2019


Space Systems Passive Common Berthing Mechanism




PCBM Used for Bigelow Expandable Activity Module (BEAM)

PCBM Test Fixtures. PCBM Lift Fixture (shown above at left) used to move the ring during AI&T and PCBM Rotation Fixture (shown at right), proof loaded at two times over expected maximum mass.

PCBM During In-flight Mate with ACBM and Drawing of Common Berthing Mechanism Subsystems

Space Systems






Sierra Nevada Corporation (SNC) Space Systems provides highly scalable power systems with power ranges from 10 W to 10 kW. SNC offers end-to-end electric power systems (EPS) consisting of fully assembled and tested solar arrays, solar array drives, slip rings, hinges, hold down mechanisms, power electronics, batteries, and motor control electronics. Our engineering teams have the expertise and experience to define, analyze, and test complete power systems utilizing state-of-the-art tools and integration equipment. Our heritage and scalable power systems can be tailored to fit a wide variety of mission options with reduced cost and risk by incorporating existing qualified and flight-proven designs. SNC has heritage EPS designs ranging from 28 V to 125 V, with power from 500 W to 3,000 W.

Industry-First Innovation

SNC has developed an automated solar array manufacturing process utilizing Surface Mount Technology (SMT) to significantly reduce the cost of space power. This patent-pending technology enables an unprecedented improvement in watts-per-area, reliability, and solar array lead time. SNC’s team of engineers, along with strategic industry partners, has developed an all-back-side-contact solar cell that enables solar array assembly through a standard pick-and-place operation. This technology results in a zero-touch labor solution and a significant improvement in overall solar array performance.

The qualification flight of the solar array is operational and already providing 25 percent more power to its host spacecraft than a conventional solar array designed for the same application.

Catalog data sheets for Sierra Nevada Corporation’s Electrical Power Systems technology area include:

C14-750 W Solar Array Drive Assembly (SADA) (See Pointing Systems and Motion Control section)

Cell Shorting Device (CSD) Battery Switch

Cubesat Solar Array

Microsat Articulated Solar Array System

Microsat Rigid Panel Solar Array System

Smallsat Solar Array System

T25 Incremental Rotary Actuator (See Pointing Systems and Motion Control section)

Space Systems

Cell Shorting Device Battery Switch





Design Description

Sierra Nevada Corporation’s (SNC) Space Systems Cell Shorting Device (CSD) Battery Switch is a robust, spaceflight-proven mechanism that passively removes a cell from a spacecraft battery’s electrical circuit. The CSD shorts across the cell terminals once the cell begins to fail (or has failed) and voltage has been driven into reversal.

The device is a mechanical switch that closes when a spring-loaded latch is released by a small paraffin actuator. Different from standard SNC actuators, which use a heater to melt the paraffin, the CSD actuator uses diodes directly attached to the actuator body. Since the diodes only allow current to flow in one direction, during normal operation no current flows through the CSD. When the cell goes into voltage reversal, current is allowed to flow through the CSD and the diodes. As the current level increases, the temperature of the diodes increases and melts the paraffin. The expanding paraffin extends the actuator output shaft, which releases the latch mechanism after a period of 10 seconds to 1 minute (depending on temperature and current level). Once the latch is released, a compression spring drives a wedge contact between the two fixed contacts, closing the circuit and shorting the cell across the terminals.

Initially designed to attach directly to the terminals, the mounting options for the CSD can be changed depending on the cell configuration and customer requirements. The CSD works on both Ni-H2 and Li-ion batteries.

Features

Mounting interface easily configurable Simple, high-reliability operation

Passive operation requires no control electronics Small size and low-mass package

Note: All dimensions above are in inches.


Space Systems





Applications

Spacecraft battery cells that require a safe cell battery switch to bypass or remove faulty cells that fail or begin to fail

Heritage Programs

Amazonas 3 (an Hispasat group of Spanish communication satellites)

Intermediate Circular Orbit (ICO) communications satellite

Satmex 6 and 8 (Satélites Mexicanos)

Anik G1 (a fixed satellite services multi-mission satellite; Telesat, Canada)

Intelsat 14, 17, 19, and 20 (International Telecommunications communication satellites)

SES Sirius 5 (a Society of European Satellites)

AsiaSat 5 and 7 (Chinese communication satellites)

iPSTAR (a Thailand geostationary communications satellite)

Spainsat (Spanish Ministry of Defense communications satellite)

DirecTV-9 (U.S. geostationary communications satellite)

Jupiter (Hughes Network Systems, U.S. communications satellite)

Superbird 7 (a Japanese communications satellite)

EchoStar XI, XIV, XV, and XVI (U.S. communications satellites)

New Skies Satellites (NSS) 12 and 14 (now SES World Skies; Dutch communications satellites)

Telstar 11N and 14R (broad Ku-band communications satellites Telesat, Canada)

Galaxy 16, 18, and 19 (U.S. communications satellites)

Nimiq 5 and 6 (Telesat, Canada communications satellites)

XM5 (a digital audio radio service satellite)

Hispasat 1E (a Spanish communications satellite)

QuetzSat (a Mexican geostationary communications satellite)

Product Specifications

U.S. SI

Mechanical

Envelope dimensions 1.85 in x 3.26 in x 0.63 in 4.69 cm x 8.27 cm x 1.59 cm

Mass < 2.3 oz < 65 grams

Life cycles Single on-orbit operation

Operation time (with 60 A @ ambient temp/pressure) ~ 25 s

Electrical

Forward voltage drop, Vf (@ 100 A, 300 µsec pulse) < 0.65 Vdc

Reverse leakage current, Ir (@ 30 Vdc) < 30 mA

Case insulation (@ 250 Vdc) > 100 MΩ

Closed circuit resistance (@ 60 A, ambient temp/pressure) < 0.54 mΩ

Switch may activate voltage (@ 95 A) > 0.16 Vdc but < 0.70 Vdc

Switch must activate current ≥ 20 A

Fuse no blow Continuously @ 110 A

Fuse must blow < 1 s @ 1,300 A; < 0.1 s @ 2,500 A

Thermal

Operating temperatures +14 °F to +113 °F

Nonoperating temperatures -13 °F to +167 °F

Paraffin non-op temp (standard) +176 °F

History

More than 100 million hours on-orbit (through May 2013) More than 2,900 units on 42 spacecraft (through May 2013)

Note: This data is for information only and subject to change. Contact Sierra Nevada Corporation for design data.

Space Systems

Cubesat Solar Array System




Cubesat Solar Array System—13 W Surface Mount Technology

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems 13 W Surface Mount Technology (SMT) Solar Array System provides highly scalable satellite power systems with power ranges from 10 W to 10 kW. SNC offers end-to-end electric power solutions that consist of fully assembled and tested solar array wings, solar array drives, slip rings, power control and distribution electronics, batteries, and motor control electronics in a wide variety of configurations to meet various mission requirements. SNC has provided systems, subsystems, and components on more than 450 space missions.

SNC’s team of experts developed a new, patent-pending, manufacturing technology that automates cell laydown and assembly of the solar array. This new technology offers several advantages over the conventional manufacturing approach including increased watts per area, increased watts per kilogram, and lower dollars per watt. SNC has teamed with an innovative photovoltaic solar cell manufacturing company to create an industry first all-back-side-contact solar cell that enables automated assembly through standard electronics manufacturing techniques (surface mount pick-and-place technology). This process eliminates all touch labor associated with assembling a solar array and has drastically reduced cost and significantly improved reliability.

SNC’s approach also reduces the design labor content associated with producing a solar array. Complex cell stringing, laydown, diode board, return board, and interconnect wiring have all been replaced by one Printed Circuit Board (PCB) drawing. Engineering

drawings associated with templates, tooling, fixturing, and other manufacturing aids have been completely eliminated. This reduction in nonrecurring engineering (NRE)

allows SNC to design, fabricate, inspect, and test a complete solar array 3 to 6 months from contract award, resulting in significant mission benefit. The solar array is no longer a pacing item on the program and late design changes in power requirements can be easily incorporated.

SNC was contracted to provide the solar array for the AFRL Satellite for High Accuracy Radar Calibration (SHARC) program on May 26, 2016. SNC delivered a fully integrated and tested solar array to AFRL on July 26, 2016—a total program duration of 2 months. The SHARC solar array is a 5U cubesat array that generates approximately 13 W at the Beginning of Life (BOL). By utilizing SNC’s technology, the SHARC program benefited from a 45 percent increase in total spacecraft power due to the exceptional packing factor of the solar cell geometry. With this small cell size, SNC significantly increases the overall cell packing factor which dramatically improves the total watts per area on a given panel size. The SHARC program launched in 2017 and the SMT is already providing 25 percent more power than a conventional solar array designed for the same application.

Dimensions


SHARC Program for the 5U Cubesat Small Satellite. This program used our Cubesat Solar Array System.

Credit: NASA and NanoRacks, LLC.

SHARC Solar Array

Space Systems

Cubesat Solar Array System




Features

Scalable power system with best-in-class watts/area High-efficiency 3J Gallium Arsenide cells

Very short lead time from design to delivery Low mass

Zero touch labor Low-cost automated assembly

Low NRE through automation High reliability (no touch labor)

Applications

Low-cost, highly scalable satellite power systems Custom power systems with ranges from 10 W to 10 kW

Heritage Programs

Satellite for High Accuracy Radar Calibration (SHARC) program


U.S. SI

Mechanical

Envelope dimensions 22.2 in x 3.4 in 564 mm x 86.4 mm

Mass .39 lb .175 kg

Life cycles 5,000 thermal cycles

Coverglass Proprietary

Substrates Printed Circuit Board

Temperature sensors 1

Electrical

Cell type Triple Junction Gallium Arsenide

Number of strings 61

Number of cells per string 5 cells in series

Number of panels 1

Power End of Life (BOL) 13 W

Cell efficiency Beginning of Life (BOL) 30%

Voltage open circuit (Voc) @ 28 C BOL 13.2 V per section

Current under short circuit (Isc) @ 28 C BOL .40 A per section

Voltage maximum power (Vmp) @ 28 C BOL 11.7 V per section

Current at maximum power (Imp ) @ 28 C BOL .40 A per section

Maximum power (Pmax) @ 28 C BOL 4.4 W per section

Thermal

Test temperature range -166 °F to +288 °F -110 °C to +142 °C


Space Systems Microsat Articulated Solar Array System




Microsat Articulated Solar Array System— 400 W Articulated Array

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems provides highly scalable satellite power systems with power ranges from 10 W to 10 kW. Providing end-to-end electric power solutions, SNC’s systems consist of fully assembled and tested solar array wings, solar array drives, slip rings, power control and distribution electronics, batteries, and motor control electronics in a wide variety of configurations to meet various mission requirements. With a long and successful heritage, SNC has provided systems, subsystems, and components on more than 450 space missions. More recently, SNC has developed, qualified, and manufactured the solar arrays for the STPSat-5 mission. Each wing consists of two deployable panels for a total power generation of 414 W at the Beginning of Life (BOL).

SNC experts conducted solar cell stringing and laydown for the STPSat-5 panels. Coverglass interconnected cells (CIC) were purchased from a heritage space solar cell manufacturer and integrated on to the panels entirely by

SNC. Front and backside wire harness was also integrated at SNC offering a turnkey solution to the end customer. In addition, SNC has the capability to perform cell laydown from any solar cell provider. This capability allows SNC to be cell agnostic when it comes to developing the overall power system resulting in a lower cost, reliable delivery schedule, and the best technical solution to the end customer.

The substrate panels are a typical construction of M55J/EX1515 face sheets bonded to a low-density 5056 aluminum perforated honeycomb core with a Kapton cover for the cell installation surface. The STPSat-5 spacecraft consists of two deployable wings with two panels each for a total of four panels per spacecraft. Each panel

measures approximately 20 inches by 28 inches. Two hold down and release mechanisms (HDRM) restrain each wing in the stowed condition through cup and cone shear features that are incorporated into each panel. Following release, spring-driven hinges with integral dampers passively extend the array in a controlled and predictable fashion. Each solar array wing stows completely within the allowable envelope with a predicted stowed first mode frequency of 53 Hz and a deployed frequency of 3 Hz.

Dimensions


STPSat-5 Spacecraft Uses Articulated Array System

STPSat-5 Panel

Deployed Stowed

Space Systems Microsat Articulated Solar Array System




Features

Scalable power system based on existing design High-efficiency Gallium Arsenide cells

Complete power system solution Low mass

High-reliability solar cells Customizable

Heritage flight-proven design minimizes nonrecurring engineering (NRE)

Heritage mechanisms

Applications


Heritage Programs

ORBCOMM Generation 2 (OG2) Tactical Satellite (TacSat-2)

Demonstration and Science Experiment (DSX) Space Test Program Satellite (STPSat-5) (ongoing)


U.S. SI

Mechanical

Envelope dimensions (deployed) 50.6 in x 27.9 in 1,285 mm x 706 mm

Envelope dimensions (stowed) 23.6 in x 27.9 in 600 mm x 706 mm

Mass (with Yoke) per wing 8.2 lb 3.7 kg


Coverglass Qioptiq 4 mil CMG/AR

Substrates M55J 7.5 mil facesheets, .390-inch perforated core, 2 mil Kapton

Temperature sensors None

Electrical




Number of panels 4


Cell efficiency Beginning of Life (BOL) 29.3%

Voltage open circuit (Voc) @ 28 C BOL 47.5 V per section

Current under short circuit (Isc) @ 28 C BOL 1.5 A per section

Voltage maximum power (Vmp) @ 28 C BOL 42.5 V per section

Current at maximum power (Imp ) @ 28 C BOL 1.5 A per section

Maximum power (Pmax) @ 28 C BOL 62.1 W per section

Thermal



Space Systems Microsat Rigid Panel Solar Array System




Microsat Rigid Panel Solar Array System—250 W Deployable Array

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems provides highly scalable satellite power systems with power ranges from 10 W to 10 kW. Providing end-to-end electric power solutions, SNC’s systems consist of fully assembled and tested solar array wings, solar array drives, slip rings, power control and distribution electronics, batteries, and motor control electronics in a wide variety of configurations to meet various mission requirements. With a long and successful heritage, SNC has provided systems, subsystems, and components on more than 450 space missions. More recently, SNC’s team of experts have developed, qualified, and delivered eight solar array assemblies capable of delivering 267 W each at the Beginning of Life (BOL) to NASA Langley for the Cyclone Global Navigation Satellite System (CYGNSS) hurricane-forecasting constellation.

The SNC solar array design utilizes industry standard high-efficiency triple-junction solar cells with extensive flight heritage. SNC’s in-house experts build upon this flight heritage or develop new designs or customized new systems to meet customer-specific requirements and mission constraints. Our power engineers have developed standardized tools and processes for performing rapid power analysis while incorporating detailed thermal and radiation models. SNC incorporates multiple solar cell sizes and suppliers to reduce the overall recurring cost of solar power. For each NASA CYGNSS spacecraft, the solar assembly consists of four body-mounted panels and two deployable wings for a total of eight panels per spacecraft. Each panel measures approximately 9 inches by 20 inches. These substrate panels are a typical construction of M55J/EX1515 face sheets bonded to a low-density 5056 aluminum perforated honeycomb core with a Kapton cover for the cell installation surface. One hold down and release mechanism (HDRM) restrains each wing in the stowed

condition through cup/cone shear features that are incorporated into each panel. Following release, spring-driven hinges passively extend the array into the fully deployed configuration. Each solar array wing stows completely within the allowable envelope with a predicted stowed first mode frequency of 312 Hz and a deployed frequency of 6.68 Hz.

SNC performs in-house random and sine vibration, thermal vacuum, and thermal cycle testing. Our engineers subjected the CYGNSS array to rigorous in-house environmental, deployment, and electrical testing. In addition, SNC has the capability in-house to perform Large Area Pulsed Solar Simulator (LAPSS) testing on a variety of panel sizes.

Dimensions


The CYGNSS Spacecraft Uses Deployable Rigid Panel Solar Array System Credit: NASA

Stowed CYGNSS Wing

Space Systems Microsat Rigid Panel Solar Array System




Features



High-reliability solar cells Customizable


Heritage mechanisms

Applications


Heritage Programs


Demonstration and Science Experiment (DSX) Cyclone Global Navigation Satellite System (CYGNSS)


U.S. SI

Mechanical

Envelope dimensions (deployed) 29.0 in x 20.0 in 750 mm x 508 mm

Envelope dimensions (stowed) 10.5 in x 20.0 in 265.7 mm x 508 mm

Mass 7.1 lb 3.2 kg



Substrates M55J 7.5 mil facesheets, .250-inch perforated core, 2 mil Kapton

Temperature sensors 1 Platinum Resistance Thermometer (PRT) per panel

Electrical


Number of strings 8

Number of cells per string 23 cells in series (Ram/Wake), 35 cells in series (Zenith)

Number of panels 8


Cell efficiency Beginning of Life 29.2%

Voltage open circuit (Voc) 61.9 V Ram/Wake, 94.4 V Zenith

Current under short circuit (Isc) .46 A per panel

Voltage maximum power (Vmp) 53.9 V Ram/Wake, 83.1 V Zenith

Current at maximum power (Imp ) .44 A per panel

Maximum power (Pmax) 23.6 W Ram/Wake, 36.6 W Zenith

Thermal



Space Systems Smallsat Solar Array System




Smallsat Solar Array System—780 W Articulated Array

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems provides highly scalable satellite power systems with power ranges from 10 W to 10 kW. Providing end-to-end electric power solutions, SNC’s systems consist of fully assembled and tested solar array wings, solar array drives, slip rings, power control and distribution electronics, batteries, and motor control electronics in a wide variety of options to meet various mission requirements. With a long heritage of success, SNC has provided systems, subsystems, and components on more than 450 space missions. More recently, SNC developed, qualified, and delivered 18 solar array assemblies capable of delivering 780 W each at the Beginning of Life for the ORBCOMM Generation 2 (OG2) program.

Our in-house experts iterate heritage designs to meet specific requirements or design new complete systems in support of various mission constraints. Our power engineers have developed standardized tools and processes for performing rapid power analysis while incorporating detailed thermal and radiation models.

The SNC solar array utilizes industry-standard, high-efficiency triple-junction solar cells with extensive flight heritage. SNC incorporates multiple solar cell sizes and suppliers to reduce the overall recurring cost of solar power. The substrate panels are a typical construction of M55J/EX1515 face sheets bonded to a low-density 5056 aluminum perforated honeycomb core with a Kapton cover for the cell installation surface. The standard panel dimensions for a 750 W array is approximately 40.6 inches by 33.4 inches

with an overall array-deployed length of approximately 105.2 inches.

Four hold down and release mechanisms (HDRM) restrain each wing in the stowed condition through cup/cone shear features that are incorporated into each panel. Following release, spring-driven hinges with integral dampers passively extend the array in a controlled and predictable fashion. Each solar array wing stows completely within the allowable envelope with a predicted stowed first mode frequency of 60 Hz. SNC can tailor the Yoke design, HDRM locations, and panel aspect ratio to accommodate the spacecraft bus design.

Solar arrays undergo rigorous environmental, deployment, and electrical tests at SNC. Depending on the size of the array, SNC performs in-house random and sine vibration, thermal vacuum, and thermal cycle testing. Before and after each test, solar arrays are subjected to a Large Area Pulsed Solar Simulator (LAPSS). SNC has the capability in-house to perform LAPSS testing on a variety of panel sizes.

Dimensions


OG2 Deployed Array

OG2 Satellite

Space Systems Smallsat Solar Array System




Features



High reliability solar cells Customizable


Heritage mechanisms

Applications


Heritage Programs


Demonstration and Science Experiment (DSX) Cyclone Global Navigation Satellite System (CYGNSS) (ongoing contract)


U.S. SI

Mechanical

Envelope dimensions (deployed) 105.2 in x 40.6 in 2,672 mm x 1,031 mm

Envelope dimensions (stowed) 33.4 in x 40.6 in 848 mm x 1,031 mm

Mass 35.3 lb 16 kg



Substrates M55J 15 mil facesheets, .375-inch perforated core, 2 mil Kapton

Temperatures sensors 1 Platinum Resistance Thermometer (PRT) per panel

Electrical




Number of panels 3

Power End of Life (EOL) (OG2 mission) 636 W

Cell efficiency Beginning of Life (BOL) 29.2%

Voltage open circuit (Voc) @ 60 C EOL 38.5 V

Current under short circuit (Isc) @ 60 C EOL 13.3 A

Voltage maximum power (Vmp) @ 60 C EOL 33.8 V

Current at maximum power (Imp ) @ 60 C EOL 12.8 A

Maximum power (Pmax) @ 60 C EOL 432.9 W

Thermal



Space Systems Flight Control and Thrust Vector Control Systems




Flight Control Systems (FCS) and Thrust Vector Control (TVC) Systems

Sierra Nevada Corporation’s (SNC) Space Systems Flight Control Systems (FCS) and Thrust Vector Control (TVC) Systems leverage our extensive experience in space-qualified actuator and electronics design. The Dream Chaser vehicle’s electro-mechanical TVC and Flight Control Systems were designed in-house at SNC to very demanding requirements leveraging spaceflight-proven hardware and engineering methods. SNC TVC Systems are designed to meet complete vehicle control requirements with highly scalable actuators and electronics, thus minimizing cost and schedule. In addition to entire TVC systems, SNC's TVC actuators can be used as a cost-effective and reliable replacement for existing TVC system actuators.

Catalog data sheets for Sierra Nevada Corporation’s Flight and Thrust Vector Control Systems technology area include:

Flight Control and Thrust Vector Control Systems

Space Systems


©2020 Sierra Nevada Corporation This Product is Export Controlled Under the International Traffic in Arms Regulations (ITAR) 31



Flight Control (FCS) and Thrust Vector Control Systems (TVC)

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems provides electromechanical Flight Control and Thrust Vector Control (TVC) Systems designed for spacecraft, launch vehicles, and missile systems. SNC’s control systems use high-performance linear electromechanical actuators and control electronics to provide customers with total system solutions for complex requirements. SNC’s engineering staff and technical heritage in electromechanical mechanisms uniquely position us within the aerospace community to provide these types of system solutions and precision mechanisms.

SNC’s electromechanical control systems offer several advantages over hydraulic systems, such as excellent long-term storage, low maintenance, and reduced mass. In addition, our electromechanical design lowers risk of hydraulic fluid leakage and contamination, providing our customers with simple and clean solutions for integration.

SNC is an industry leader in the design and manufacture of numerous precision space mechanisms and complex spacecraft systems and subsystems. As a proven, space-qualified systems integrator, we possess the technological expertise to develop complete systems and ensure customer-specific requirements are achieved.

Features

High-performance systems build on SNC’s hardware heritage

Collaborative and responsive working relationships, resulting in high customer satisfaction

Complete system solutions with integrated control electronics for precise and reliable performance

A diverse team of industry experts offering fully engineered solutions

Aerospace quality materials for mass-optimized design Low maintenance, reduced mass, lower risk of leakage

Applications

Electromechanical flight surface and thrust vector control for spacecraft, launch vehicles, and missiles

Full electrical and mechanical redundant systems are available for critical spaceflight applications

Dimensions

Dream Chaser Flight Control System (FCS) Actuator L20: 22 inches

Thrust Vector Control (TVC) Actuators L11: 18 inches (left) and L2: 14 inches (right)


Electromechanical Thrust Vector Control System (L2)

Space Systems





Heritage Programs

Dream Chaser Flight Control System L20 and L13 (electrically and mechanically redundant)

Thrust Vector Control System L2 (electrically redundant)


U.S. SI

Mechanical

Envelope dimensions

(Null position)

L20: 21.5 in x 11.75 in x 5.5 in

L13: 18.0 in x 11.5 in x 5.5 in

L11: 18.1 in x 8.1 in x 5.2 in

L2: 14.0 in x 5.6 in x 3.3 in

L20: 546.1 mm x 298.5 mm x 139.7 mm

L13: 457.2 mm x 292.1 mm x 139.7 mm

L11: 459.7 mm x 205.7 mm x 132.1 mm

L2: 355.6 mm x 142.2 mm x 83.8 mm

Mass L20: < 51.0 lb

L13: < 43.5 lb

L11: < 26.0 lb

L2: < 14.0 lb

L20: < 23.13 kg

L13: < 19.73 kg

L11: < 11.79 kg

L2: < 6.35 kg

Nominal travel life L20: 7,900 in

L13: 19,350 in

L11: 250 in

L2: 5,000 in

L20: 200.66 m

L13: 491.5 m

L11: 6.35 m

L2: 127 m

Nominal operating time L20: 500 minutes

L13: 500 minutes

L11: 1.35 minutes

L2: 150 minutes

N/A

Stall Load L20: > 20,000 lbf

L13: > 13,000 lbf

L11: >11,650 lbf

L2: > 2,000 lbf

L20: > 89 kN

L13: > 57.8 kN

L11: > 51.8 kN

L2: > 8.9 kN

Range of Motion L20: ±2.25 in

L13: ±2.25 in

L11: ±0.50 in

L2: ±0.83 in

L20: ±57.1 mm

L13: ±57.1 mm

L11: ±12.7 mm

L2: ±21.1 mm

Load Speed L20: > 7.0 in/s

L13: > 10.5 in/s

L11: > 3.8 in/s

L2: > 3.0 in/s

L20: > 177.8 mm/s

L13: > 266.7 mm/s

L11: > 96.5 mm/s

L2: > 76.2 mm/s

Load Point L20: 5.0 @ 6,125 in/s @ lbf

L13: 5.0 @ 7,150 in/s @ lbf

L11: 2.6 @ 10,450 in/s @ lbf

L2: 2.8 @ 1,500 in/s @ lbf

L20: 127.0 @ 27.2 mm/s @ kN

L13: 127.0 @ 31.8 mm/s @ kN

L11: 66.0 @ 71.1 mm/s @ kN

L2: 71.1 @ 6.7 mm/s @ kN

Electrical

Load Point L20: 120/120 Vdc/Apk

L13: 120/120 Vdc/Apk

L11: 120/65 Vdc/Apk

L2: 120/10 Vdc/Apk

N/A


Space Systems

HOP Actuators and Mechanisms




High Output Paraffin Actuators and Mechanisms

Since 1987, Sierra Nevada Corporation’s product line has flown thousands of mechanisms on hundreds of space missions with a legacy of on-orbit operational success. Our very first product, the High Output Paraffin (HOP) Actuator, has become an industry standard for the gentle, low-shock release of critical spacecraft applications such as solar arrays, antennas, and payloads. HOP thermal actuators were developed to provide an alternative to conventional aerospace actuators by directly converting temperature changes to useful mechanical work. When fabricated with internal resistance heating elements, they provide an electric linear motor. For applications in which slower response times are acceptable or preferred, HOP actuators have distinct advantages over conventional approaches that include:

Resettable: can be cycled > 1,000 times

Flight hardware can be fully verified before flight

Output force to 4000 N (900 Ib)

Stroke to 10 cm

High reliability: one moving part (the actuator rod)

Can be fabricated magnetically clean

Gentle smooth stroke

Low power requirement (5 to 40 W at 28 V)

Non-explosive: minimal safety concerns

Weighs less than 30 grams

Small size

The capability of HOP thermal actuators to convert temperature changes to useful mechanical work also creates a wide variety of aerospace applications in thermal control systems, and systems that can utilize mechanical work from temperature changes or heat (solar) input. Catalog data sheets for Sierra Nevada Corporation’s High Output Paraffin (HOP) Actuators and Mechanisms product area include:

EH-3525 HOP Actuator

IH-5055/-10055 High Output Paraffin (HOP) Actuators

PP-35055 Resettable High-Force Pin Puller

PP-5501 Two-Position Latching Actuator

RO-9015 Two-Position Rotary Latching Actuator

SP-5025 High Output Paraffin (HOP) Pin Puller


Space Systems

EH-3525 High Output Paraffin Actuator

©2020 Sierra Nevada Corporation This Product is Export Controlled the Under Export Administration Regulations (EAR) 34



EH-3525 High Output Paraffin (HOP) Actuator

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems has designed and developed the External Heater (EH) High Output Paraffin (HOP) actuator (linear motor) to complement the IH-5055 series of actuators. These HOP actuators are designed for extreme cleanliness applications and incorporate a welded bellows for a sealed, zero-outgassing prime mover. The EH-3525 uses a redundant external heating element to melt the paraffin charge in the actuator. When melted, the paraffin expands and creates hydrostatic pressure, which is transformed into a gentle, high-force shaft extension. The welded-bellows assembly incorporates an internal return spring and hard stop, which results in a self-resetting actuator.

The extreme cleanliness of the actuators meets the most stringent NASA requirements making them suitable for ultra-clean applications. HOP technology is easily scaled to meet a variety of customer size and application requirements. SNC provides multiple versions of this welded-bellows, seal-type actuator. The overall function time is dependent upon load, power input, and environmental conditions.

Features

Gentle, smooth extension Built-in hard stop

Hermetically sealed High force-to-mass ratio

Stainless steel case Self-resetting

Overpressure safety device Nonexplosive

Fully redundant heaters Minimal safety requirements

Dimensions


EH-3525 HOP Actuator. The EH-3525 HOP Actuator incorporates an internal welded bellows, providing a built-in return spring while meeting the most stringent cleanliness requirements.

Space Systems

EH-3525 High Output Paraffin Actuator




Applications

Linear motor actuator scalable to meet a variety of customer size and application requirements

Spacecraft environments requiring extreme cleanliness applications

Heritage Programs

Stratospheric Aerosol and Gas Experiment (SAGE) III B-Sat

Spitzer Defense Meteorological Satellite Program (DMSP)

Multi-User System for Earth Sensing (MUSES-C) Korean Multi-Purpose Satellite (KOMPSAT)

Clementine Mars Phoenix

Chandra Cassini

Earth Observing System (EOS) Terra Solar and Heliospheric Observatory (SOHO)


U.S. SI

Mechanical

Mass 1.24 oz 35 grams

Response time in air (35-lb load, 28 Vdc) ~200 s @ +75 °F ~200 s @ +24 °C

Full stroke 0.25 in 0.635 cm

Nominal output force 35 lbf 156 N

Load of overpressure function > 105 lbf > 467 N

Lifetime (nominal load) 500 cycles

Electrical

Power 5 W @ 28 V

Voltage range 22 Vdc to 34 Vdc

Wiring/insulation 4 leads 26 AWG in accordance with Mil-W-22759/33

Heater resistance 2 x 157 ± 2% Ω

Thermal

Operating temperature range -76 °F to +176 °F -60 °C to +80 °C

Nonoperating temperature -184 °F to +176 °F -120 °C to +80 °C

Nonactuation temperatures +176 °F +80 °C


Space Systems

IH-5055/-10055 High Output Paraffin Actuators




IH-5055/-10055 High Output Paraffin (HOP) Actuators

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems IH-5055/-10055 High Output Paraffin (HOP) actuators (or linear motors) are electrically powered resettable devices that generate high-force and long-stroke linear motion.

Redundant Internal Heaters (IH) melt a paraffin charge inside the actuator. When melted, the paraffin expands and creates hydrostatic pressure that is transformed into a gentle, high-force shaft extension. A proprietary design incorporating a squeeze boot seals the paraffin and prevents any possibility of material release. Negligible outgassing makes these actuators suitable for most contamination-sensitive applications.

This HOP technology is easily scaled to meet a variety of customer size and application requirements. SNC provides multiple versions of this squeeze boot seal-type actuator. The overall function time is dependent upon load, power input, and environmental conditions.

Features

Gentle, smooth extension High force-to-mass ratio

Titanium case Easily reset with no disassembly or refurbishment

Overpressure safety device Nonexplosive

Fully redundant heaters Minimal safety requirements

Ferrule or flange mount available

Dimensions


IH-5055/-10055 High Output Paraffin (HOP) Actuator. This actuator is shown with a standard thermal insulation-mounting ferrule. The actuator is also available with optional flange mount.

Space Systems

IH-5055/-10055 High Output Paraffin Actuators




Heritage Programs (IH-5055)

Global Positioning Satellite (GPS-2F) Earth Observing System (EOS)

Mars Phoenix Lander Television Infrared Observation Satellite (TIROS)

Indostar II Thermal Emission Spectrometer (TES)

Spitzer Solar Terrestrial Relations Observatory (STEREO)

Cassini Solar and Heliospheric Observatory (SOHO)

Galaxy International Telecommunications Satellite Organization (Intelsat)

SES (Society of European Satellites) Koreasat

MexSat (Mexico's next-generation mobile satellite system)

Thaicom


U.S. SI

Mechanical


Response time in air (50-lb load, 28 Vdc) ~210 s @ +75 °F ~210 s @ +24 °C

Full stroke 0.55 in 1.40 cm

Nominal output force IH-5055 = 50 lbf, IH-10055 = 100 lbf 444.8 N

Load of overpressure function IH-5055 > 100 lbf, IH-10055 > 150 lbf > 667 N


Lifetime 1,000 cycles @ 50 lbf, 100 cycles @ 100 lbf

Electrical

Power 10 W @ 28 V

Voltage range 22 to 44 Vdc


Heater resistance 2x 78 ± 3% Ω

Thermal

Operating temperature range -85 °F to +176 °F -65 °C to +80 °C





Applications

Spacecraft launch locks Solar array hold down and release

Release of spacecraft instrument doors and covers Used in a broad number of applications as linear motors in spacecraft mechanical systems

Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems PP-35055 Pin Puller is a remotely resettable mechanism that provides high retraction force. This high-force, ultra-clean pin puller also contains an integral binary latching mechanism. These features provide a high-retraction force, high-shear pin puller that is fully resettable.

When energized, the pin is retracted and then latched in the retracted position. When re-energized, the mechanism unlatches and the pin extends. Repeated operation alternately extends and retracts the output pin. Appropriate applications include caging of gimbaled instruments, release of high loads and restraint of rotating hardware.

The heart of the PP-35055 is an EH-35055 high force High Output Paraffin (HOP) actuator providing a maximum 350 lbf of retraction force to the output pin. This hermetic bellows-type seal actuator is coupled to a binary latch that toggles the mechanism between the two latched conditions (extended and retracted) when repeatedly operated. Position telemetry is provided by single or redundant limit switches for both extended and retracted conditions.

Features

High-static shear-load capability Remotely resettable

High available retraction force Hermetically sealed

Simple control Gentle operation

Dimensions



Space Systems





Applications

Mechanism caging and uncaging Release of high loads

Restraint of rotating equipment Binary positioning

Heritage Programs

International Space Station (Beta Joints) Meteosat Second Generation (MSG) SEVIRI Instrument

International Space Station (Solar Experiment)


U.S. SI

Mechanical


Response time ~360 sec. @ 24 °C (75 °F)

Retraction force 350 max / 250 lbf min 1,557 N max / 1,112 N min

Extension force 3 lbf max 13.3 N min

Shear load capability 1,000 lbf static 4,448 N

Lifetime 500+ cycles

Control Simple on/off

Latched stroke .5 in 1.27 cm

Electrical/Thermal

Power/voltage (nominal) 20 W @ 28 V

Operating environment -22 °F to +176 °F -30 °C to +80 °C


Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems PP-5501 is a remotely resettable mechanism that provides shaft extension and retraction, with zero-power latching in the fully extended and retracted positions. Appropriate applications include caging of mechanisms, instrument cover driving, slow-speed aperture shuttering, and valve opening and closing.

The heart of the PP-5501 is the SNC Space IH-5055 High Output Paraffin (HOP) actuator. Energizing the actuator drives the output shaft .54 inches, at which point the control switches change state, providing a signal to discontinue power. The shaft then retracts and latches at .45 inches of extension. The retraction force of the mechanism is supplied by redundant internal bias springs. When energized again, the output shaft extends and unlatches. Power is again interrupted, which allows the output shaft to retract to the original position.

This cycle can be repeated as many times as required to alternately extend and retract the output shaft with no power required for maintaining either latched position. Design modifications can be made to increase retraction force or modify stroke length.

Features

Gentle extension and retraction Remote operation and reset

Unpowered two-position latching Integral redundant control limit switches

Rotary version available Simple control

Dimensions

Note: All dimensions above are in inches. Threaded end optional.

PP-5501 Two-Position Latching Actuator. PP-5501 actuator is a fully resettable, ultra-clean, high-force pin puller.

Space Systems





Heritage Programs

Clementine spacecraft Solar and Heliospheric Observatory (SOHO)

Geotail spacecraft


U.S. SI

Mechanical


Response time ~200 s from +75 °F ~200 s from +24 °C

Extension force 50 lbf 222 N

Retraction force 3 lbf 13.3 N

Maximum stroke .600 in 1.524 cm

Lifetime 1000 + cycles

Control Simple on/off

Latched stroke .45 in 1.14 cm

Electrical

Power/voltage (nominal) 10 W @ 28 V

Operating environment -76 °F to -176 °F -60 °C to +80 °C


Applications

Mechanism caging and uncaging Two-position valve operation

Slow-speed aperture shuttering Slow-speed valve opening/closing

Actuation of instrument cover Optical shutter positioning

Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems RO-9015 Two-Position Rotary Latching Actuator provides a high-torque rotational output. Applications for this actuator latch include solar panel deployment, mirror positioning, and multiple operations of covers and doors.

This mechanism uses a high output paraffin (HOP) force to generate rotational motion in one direction. A return spring drives the mechanism in the opposite direction. Zero-power latching is provided in both of the fully rotated positions. The RO-9015 features operation torque and latching that is designed for spring-biased components such as instrument covers. Energizing the mechanism initiates heating of the HOP actuator. When the paraffin melting temperature is reached, the output shaft begins to rotate in the drive direction. Drive torque is provided as the shaft rotates through its rotational range. At the end of rotation, the binary latch engages. Limit switches then signal to disconnect power. To reverse the rotation, power is again supplied to the HOP actuator. After a brief warming period, the binary latch disengages. As the actuator cools, the output shaft of the mechanism slowly rotates back to the original position. Repeated operation of the actuator cycles the mechanism between the two latched positions.

Features

Remote reset operation No power required to hold either latched position

Smooth rotary motion Integral redundant control limit switches

High torque-to-mass ratio

Dimensions


RO-9015 Two-Position Rotary Latching Actuator. Latching actuator provides high-torque rotational output.

Space Systems





Applications

Solar panel deployment Mirror positioning

Multiple operations of covers and doors

Heritage Programs

Proprietary program–used to open and close an instrument cover


U.S. SI

Mechanical


Response time ~210 sec. from 24°C (75°F)

Output torque 15 in-lbf 1.7 N-m

Available rotation 90° to 180°

Lifetime 1000+ cycles

Control requirements Simple On/Off operation

Electrical

Power/Voltage 10 W @ 28 V

Thermal

Operating environment -148 °F to +176 °F -100 C° to +80°C


Space Systems

SP-5025 High Output Paraffin Pin Puller





Design Description

Sierra Nevada Corporation’s (SNC) Space Systems Shut-off Pin Puller (SP-5025) High Output Paraffin (HOP) actuator is an auto shut-off pin puller. The SP-5025 uses a redundant external heating element to melt the paraffin charge in the actuator. When melted, the paraffin expands and creates hydrostatic pressure that is transformed into a gentle, high-force pin retraction. The SP-5025 includes fully redundant internal circuit interrupts that can discontinue power to the actuator once full retraction has been reached. Alternatively, the circuit interrupts can provide a switch signal to allow the user to power off the actuator, depending upon the chosen wiring configuration.

This design reduces overall system cost by simplifying control requirements. The SP-5025 may be powered by a single timed power pulse to one of the fully redundant heater circuits. The dual heaters and dual circuit interrupts can be wired by the user to provide for autonomous or interactive control system designs.

The pin puller is resettable in place using the appropriate reset tool. The overall function time is dependent upon load, power input, and environmental conditions.

Features

Integral circuit interrupts Resettable without refurbishment

Simple control system Nonexplosive

Gentle, high-force retraction Minimal safety requirements

Fully redundant heaters Includes thermal isolation washers

Dimensions


SP-5025 High Output Paraffin (HOP) Actuator

Space Systems





Applications


Release of spacecraft instrument doors and covers Used in a broad number of applications as linear motors in spacecraft mechanical systems

Heritage Programs

Thermal Emission Spectrometer (TES) Cassiope

Space-Based Infrared System (SBIRS) Highly Elliptical Orbit (HEO)

Republic of China Satellite-2 (ROCSAT-2) (renamed FORMOSAT-2)

SBIRS Geosynchronous Earth Orbit (GEO) GeoEye 1

Galaxy Evolution Explorer (GALEX) OrbView-3 & -4

H2 Transfer Vehicle (Hypersonic Transfer Vehicle, HTV)


U.S. SI

Mechanical

Mass 2.82 oz 80.0 g

Response time in air (50 lb, 28 Vdc) ~150 s @ +75 °F ~150 s @ +24 °C

Stroke 0.310 in 0.787 cm

Maximum retraction force 140 lbf 623 N

Maximum reset force required 15 lbf 66.7 N

Shear load capability 350 lbf quasi-static

Reset tools needed Manual reset tool EP-7032 or

Pneumatic tool EP-7056

Reset time <10 min


Electrical

Power 15 W @ 28 V


Heater resistance 2x 52.3 ± 5% Ω


Redundancy Heaters and circuit interrupts

Thermal

Operating temperatures -85 °F to + 176 °F -65 °C to +80 °C

Nonoperating temperatures -319 °F to +176 °F -195 °C to +80 °C



Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems auto-shut off Pin Puller (SP-5085) is a High Output Paraffin (HOP) actuator device, which translates electrical power into a smooth and predictable linear retraction of the output shaft. The SP-5085 HOP automatically disables the power to the redundant heaters upon full retraction eliminating the risk of being over-energized. The unit is non-pyro, field resettable, and capable of hundreds of actuations without refurbishment.

The unit is a high reliability device that has been used in critical applications on many space missions with 100% success. Hundreds of units have been produced over the past 30 years for a wide variety of space applications including instrument cover systems, solar arrays, and other spacecraft subsystems.

Features

Integral circuit interrupts Resettable without refurbishment

Simple control system Nonexplosive

Gentle, high-force retraction Minimal safety requirements

Fully redundant heaters Includes thermal isolation washers

Dimensions


Applications


Release of spacecraft instrument doors and covers Used in a broad number of applications such as linear motors in spacecraft mechanical systems

SP-5085 High Output Paraffin (HOP) Actuator

Space Systems





Heritage Programs

NASA Docking System Worldview

Visible Infrared Imaging Radiometer Suite (VIIRS) Scientific Satellite (SCISAT)

Restricted Programs Atmospheric Chemistry Experiment (ACE)


U.S. SI

Mechanical

Mass 3.70 oz 105.0 g

Response time in air (50 lb, 28 Vdc) ~220 s @ +75 °F ~220 s @ +24 °C

Stroke 0.850 in 2.16 cm

Maximum retraction force 100 lbf 445 N

Maximum reset force required 15 lbf 66.7 N

Shear load capability 120 lbf quasi-static 534 N quasi-static

Reset tools needed Manual reset tool EP-14880 or

Pneumatic tool EP-7056

Reset time <10 min


Electrical

Power 25 W @ 28 V


Heater resistance 2x 31.4 ± 5% Ω


Redundancy Heaters and circuit interrupts

Thermal

Operating temperatures -85 °F to +176 °F -65 °C to +80 °C




Space Systems






Introduction

Sierra Nevada Corporation’s (SNC) Space Systems instrument door and cover systems provide a simple, robust, heritage solution for most spacecraft applications. Sensitive spacecraft instruments can require a wide range of protection from external threats such as dust particles, contaminants, and stray light. Some systems even require a hard space vacuum to be preserved prior to use in space to maintain sensor integrity.

SNC's instrument doors and covers are turnkey, providing a complete end-to-end solution that can be simply bolted onto the spacecraft instrument aperture interface. Our cover systems are typically comprised of four primary elements: the door and cover structure; the latch mechanism; the seal system, and the hinge system. A more detailed data sheet provides more specific applications and features:


Space Systems






Sierra Nevada Corporation’s (SNC) Space Systems instrument door and cover systems provide a simple, robust, heritage solution for most spacecraft applications. Sensitive spacecraft instruments can require a wide range of protection from external threats such as dust particles, contaminants, and stray light. Some systems even require a hard space vacuum to be preserved prior to use in space to maintain sensor integrity. As both a component supplier and system integrator, SNC leverages in-house technologies and significant flight heritage to meet the most stringent requirements under extreme environments with the lowest-risk solutions.

SNC's instrument doors and covers are turnkey, providing a complete end-to-end solution that can be simply bolted onto the spacecraft instrument aperture interface. Our cover systems are typically comprised of four primary elements: the door and cover structure; the latch mechanism; the seal system, and the hinge system.

Features

Turn-key systems and mechanisms Lightweight door structures; variety of seals available

Redundant latch mechanisms with simple re-set and high reuse

Experience with a wide range of sizes from 1 inch to >3 feet in diameter

Thin-film, roll-up covers available for ultra-lightweight needs

One time open systems with positive latch out at end of travel, to motorized systems requiring many open-close cycles

Cover System Flown on Cassini. Cover systems span a wide range of programs with flight-proven heritage, providing robust solutions for most spacecraft applications.

Credit: NASA

DISCOVR EPIC Camera Door System. This door system was used on NASA’s Deep Space Climate Observatory (DISCOVR) Earth Polychromatic Imaging Camera (EPIC) instrument. Credit: Ken Kremer

Space Systems





Heritage Cover System Programs

Cassini Plasma Spectrometer (CAPS) Atmospheric Infrared Sounder (AIRS) Earthshield

Swift Ultraviolet/Optical Telescope (UVOT) and X-ray Telescope (XRT)

Europa Mass Spectrometer for Planetary Exploration (MASPEX)

Deep Space Climate Observatory (DSCOVR, formerly Triana) Earth Polychromatic Imaging Camera (EPIC)

Fast, Affordable, Science and Technology Satellite (FASTSAT) Thermospheric Temperature Imager (TTI)

Clementine Mars 2001 In-situ Propellant Production Precursor (MIP)

Earthwatch IKONOS (Space Imaging Remote Sensing System)

Cross-track Infrared Sounder (CrIS) Cooler OrbView-3 and -4 (multispectral imagery satellite)

Government Missions

Instrument Door and Cover Structure

The door and cover structure consists of lightweight, machined aluminum or composite materials. These structures are available for use on rigid doors, including door paint/tape surface preparations to reflect light and heat away from the instrument, or ultra light-weight, thin-film covers that simply un-latch and roll-up to expose the aperture.

Latch Mechanism

The latch mechanism keeps the door closed during launch and in-space loads. Simple High Output Paraffin (HOP) or Shaped Memory Alloy (SMA) actuators offer ease of use, with hundreds of operation cycles possible with zero latch refurbishment. Single string, electrically redundant and fully mechanically redundant designs are available. SNC also offers latches than can "re-latch" the door closed for multiple open-close cycle applications, as well as separation nuts for systems requiring a robust pre-load of the door prior to launch.

Seal System

The seal system keeps external environments away from the sensor. SNC has experience with seals ranging in complexity from simple labyrinth types to keep our stray light, to lightweight foam seals to keep out dust and other particulates, to O-rings with non-stiction features to hold a light differential pressure. SNC also has experience with a variety of seal approaches (knife-edge seals and others) for holding a hard space vacuum inside the cover.

Hinge System

The hinge system opens the door and exposes the sensor view and features: 1) simple, one-time open spring hinges, with or without dampers; 2) lock-out at end of rotation to preclude bounce back; and 3) motorized hinge-lines and control electronics for multiple open-close cycles.

Swift UVOT- XRT FASTSAT TTI DISCOVR EPIC Camera Door CrIS Cooler Cover (Credit: NASA)

Heritage Door and Cover Systems. Contributed doors and cover systems to a wide variety of spacecraft programs, including Swift UVOT XRT, FASTSAT TTI, DISCOVR EPIC Camera Door, and CrIS Cooler Cover, as shown above in these examples.

Space Systems






Sierra Nevada Corporation’s (SNC) Space Systems has supported both U.S. and international launch services for decades with a variety of technologies needed for reliable and gentle deployment of payloads and spacecraft into proper orbit. Devices such as the low-shock Clamp Band Opening Devices (CBOD) are now used to release dozens of primary payloads each year on nearly every major launch vehicle in the world. Other products such as our Fast-Acting Shockless Separation Nuts (FASSN) have become the go-to method for safely restraining and releasing the cargo pallet on every H2 Transfer Vehicle to assist in delivering critical equipment and supplies to the International Space Station. At a higher subsystem level, our Quick Separation (QwkSep®) clamp-band type systems are recognized as a new, robust industry standard to deploy smaller satellites and constellations at lower cost and higher reliability. And with the backing and resources of a prime integrator such as SNC, we are now able to offer larger structural systems such as our own Dream Chaser cargo module separation system as well as dispensers, adapters, and integration services required for carrying both single and multiple spacecraft onward to their mission in space.

Catalog data sheets for the Sierra Nevada Corporation’s Launch Support Products and Services technology area include:

Fast-Acting Shockless Separation Nut (FASSN) 30K

Hold Down Release Mechanism (HDRM)

Low-Shock Release Mechanism (LSRM) 5K

Microsat Deployment Module

QwkSep 15 Low-Profile Separation System


Space Systems

Fast-Acting Shockless Separation Nut 30K




Fast-Acting Shockless Separation Nut (FASSN) 30K

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems offers the Fast-Acting Shockless Separation Nut (FASSN) 30K—a space-qualified, low-shock separation nut ideal for restraining and releasing satellite and launch vehicle preloaded structural joints.

SNC’s Space Systems FASSN 30K offers a revolutionary solution to spacecraft release requirements. This technology developed jointly by SNC’s Space Systems and Lockheed Martin offers fast, gentle separation from a device that is fully re-settable without refurbishment. Designed as a drop-in replacement for existing pyrotechnic hardware, the FASSN can easily be incorporated into existing spaceflight configurations.

Using a resettable, reusable shape memory alloy (SMA) trigger instead of pyrotechnics for actuation, multiple ground operations are possible without the safety concerns associated with pyros.

When actuated, a caged flywheel is released. The high-lead threads on the bolt start the flywheel spinning, and the bolt is released in milliseconds. The strain energy of the bolt is converted into rotational energy in the flywheel, resulting in orders of magnitude less shock than a pyro release.

The FASSN is fully resettable using common tools, with no refurbishment or replacement of parts. In addition, it is scalable for most applications. The 1K, 10K, and 30K versions have all successfully flown in space.

Features

Fully resettable with no refurbishment Drop-in replacement for pyro devices

Orders of magnitude less shock than pyros Flight hardware can be repeatedly tested prior to flight

Release time supports simultaneity needs EVA back-up release feature available on bolt retractor

Dimensions

Note: All dimensions above are in inches. Bolt retractor with EVA feature shown.

FASSN 30K. The FASSN 30K device is shown here with the Extra Vehicular Activity (EVA) bolt retractor.

Space Systems

Fast-Acting Shockless Separation Nut 30K




Applications

H2 Transfer Vehicle (HTV) Cargo Pallet Restraint System (30K version)

Spacecraft Separation (10K version)

Large Telescope Barrel Cover Release (1K version)

Heritage Programs

H2 Transfer Vehicle 1, -2, -3 Restricted program


U.S. SI

Mechanical

Envelope Dimensions:

Nut:

Bolt Retractor:

5 in x 5 in x 5 in

5-in diameter x 7-in tall

127 mm x 127 mm x 127 mm

127-mm diameter x 178-mm tall

Mass:

Nut:

Bolt Retractor (EVA feature):

6.5 lbm max.

4.5 lbm max.

2.9 kg max.

2.0 kg max.

Preload 10,000 to 30,000 lbf 44.5 to 133.4 kN

Life Cycles >50 full load releases

Redundancy Full electrical

Release signal 3.6 A for 75 ms

Release time 200 msec max.

Source shock <100 G

Vibration 16.8 grms for 2 min. per axis

Reset Reset tools provided by SNC. Requires access from sides and top of FASSN nut to reset the latch and redundant actuators, and from the top of bolt retractor to insert and then preload the bolt. Super-nut provided for simple pre-load application. Force-sensing bolt (“Strainsert”) provided for real-time preload reading.

Note:

This data is for information only and subject to change. Contact Sierra Nevada Corporation for design data.

Space Systems

Hold Down Release Mechanism





Design Description

Sierra Nevada Corporation’s (SNC) Space Systems Hold Down Release Mechanism (HDRM) is a fast-acting separation nut rated to accommodate several working preloads. The HDRM series uses a conventional segmented separation nut with a redundant shape memory alloy (SMA) trigger that responds to a standard pyrotechnic firing pulse. The SMA trigger allows for fast response times with low release shock. Integral circuit interrupts open trigger circuits upon release, simplifying ground operations and flight control requirements. The HDRM resets and is ready for bolt insertion in less than 1 minute with the supplied reset pin.

The HDRM releases a standard UNF high-strength bolt. SNC’s HDRM bolt retractor (offered separately) is a flight-qualified option with a preload measurement using a calibrated load cell and spherical washer set to accommodate angular misalignment. In addition, the bolt retractor features an easily removable cover that facilitates reset.

Features

Uses wide range of initiation pulses Millisecond release

Circuit interrupt feature for simple control Low shock

Eliminates pyrotechnic safety concerns Easily reset in place with a simple tool—no refurbishment

Low mass Flight hardware can be repeatedly tested prior to flight

Redundant, resettable shape memory alloy triggers High dynamic load capability

Applications

Spacecraft-from-launch vehicle separation, solar array hold-down and release, gimbal launch locks and other satellite applications requiring a low-shock, quick release

Dimensions



Space Systems

Hold Down Release Mechanism




Heritage Programs

Space Test Program Satellite-1 (STPSat-1) Communications/Navigation Outage Forecasting System (CNOFS)

WorldView-1, -2, and -3 eXperimental Small Satellite 10 (XSS-10)

Poly Picosatellite Orbital Deployer (P-POD) European Space Agency Swarm Satellites

Advanced Extremely High Frequency (AEHF) Space Communication and Navigation Testbed (SCaN)

Cyclone Global Navigation Satellite System (CGNSS)

Small Missions for Advanced Research in Technology-1 (SMART-1)

Falconsat-1

Nanoracks Kaber Deployer Kestral Eye


U.S. SI

Mechanical

Thread 1/4-28 UNF 5/16- 24 UNF No metric equivalent

No metric equivalent

Nominal working preload (allows for operating margin and preload uncertainty)

3,400 lbf 4,800 lbf 15,125 N 21,351 N

Max. operating load capability (higher pre-load versions are currently under development; specs available upon request)

4,000 lbf max. 5,300 lbf max. 17,793 N 23,576 N

Release bolt replacement interval 15 recommended (30 qualified) for NAS1351

Misalignment capability ±1.5° OR

±0.015-inch lateral

±1.5° OR

±0.381 mm lateral

Mass 9.52 oz max. 270 g max.

Life cycles > 100 full load releases

Redundancy Full electrical, partial mechanical

Operational margins > 100%

Source shock < 400 g < 400 g (expected)

Reliability > .9999

Random vibration 36 grms

Release time 15 to 200 msec (over operational environment conditions)

Electrical

Power input Typical: 45 W @ 3.5 A @ 20 °C

Release signal range

for operating temperatures

Typical: 3.5 A, 35 msec @ 20 °C

Range: 2.3 A to 7 A, 15 msec to160 msec

SMA resistance (single circuit) 3.9 ± 0.1 @ 20 °C Ω

No-fire current 0.25 A min.

All-fire current (200 msec) 2.3 A

Lead-wire 4x 22 AWG (Mil-W-22759/33)

Thermal



Reset

Tools needed Ø.1250-inch gauge pin

Reset for HDRM <1 minute (ready for bolt insertion)


Space Systems

Low-Shock Release Mechanism 5K




Low Shock Release Mechanism (LSRM) 5K

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems Low-Shock Release Mechanism (LSRM) 5K is a simple, fully redundant and reusable low-shock producing release latch for the hold down and release of preloaded joints. The LSRM uses a conventional toggle bolt that engages a mechanically redundant latch.

The design features a unique gear and flywheel combination that creates low required energy to release a low-source shock upon actuation of the latch and release of the stored strain energy. The LSRM 5K is capable of being released with either low- or high-speed redundant actuators. It can be used as a discrete release latch or used together with multiple latches to release larger interfaces without requiring additional actuators.

The LSRM 5K (sized for a 5,000 lbf preload) successfully released an important U.S. scientific payload on-orbit in 2014. The LSRM 5K can be scaled up or down to support specific size and preload requirements.

Features

Robust and easy to use Re-settable in-situ

Mechanically and electrically redundant No parts to replace with >100 load and release cycles

Low-shock release Optional bolt catcher features available

Adaptable for use with fast-acting and slow (very low-shock) actuators (included)

Dimensions


Low Shock Release Mechanism (LSRM) 5k

Space Systems

Low-Shock Release Mechanism 5K




Applications

Spacecraft Hold Down and Release (HDRM) applications Smaller launch vehicle staging

Dispenser/adapter systems

Heritage Programs

Drag and Atmospheric Neutral Density Explorer (DANDE)


U.S. SI

Mechanical

Envelope dimensions 2.6 in x 3.6 in x 2.0 in 66 mm x 91 mm x 51 mm

Mass 1.5 lbm max. 0.52 kg max.

Preload 5,000 lb 22,241 N

Redundancy Full mechanical and electrical

Release signal 5 A for 100 milliseconds

Release time 100 msec max.

Source shock 100 g’s peak between 10 to 5,000 Hz

Operating temperature -65 °F to +160°F -54 °C to 71 °C

Shock Falcon 9 launch loads

Vibration Falcon 9 launch loads

Reset

Tools needed Standard hex and open-end wrenches

Reset time < 5 minutes

Access Requires access from two sides to reset the latch and redundant actuators, and from the top to insert and then preload the bolt.


Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems provides highly scalable satellite constellation deployment modules. Providing end-to-end solutions, SNC’s systems consist of a fully assembled and tested deployment module structure, hold down and release mechanisms (low-shock and reusable separation nuts), tailorable satellite separation springs, umbilical disconnects, separation indication features, and cabling and harnessing assemblies.

SNC’s deployment modules are available in a wide variety of configurations to meet various mission requirements. With a long and successful heritage, SNC has provided thousands of systems, subsystems, and components on hundreds of space missions. In 2016, SNC developed, qualified, and manufactured the deployment module for the CYGNSS mission. This module consists of a central tube

structure with discrete separation modules that secure and gently separate the eight CYGNSS microsatellites.

SNC experts provided a custom-engineered, design-to-specification solution that enables the entire constellation to be launched simultaneously in pairs. In addition, SNC’s heritage, fast-acting and low-shock Hold Down and Release Mechanism (HDRM) product allows for paired sets of satellites to be deployed simultaneously in an extremely soft and clean manner, in contrast to traditional pyrotechnic separation devices that create significant debris and generate high-shock loading into the spacecraft.

Dimensions

Note: All dimensions above are in inches. (Note: The origin is at the LV Interface and on the centerline of the canister. Looking at the Side View above, +X is vertical, +Y is to the left, +Z is out of the page.)

Microsat Deployment Module.Deployment Module enables all eight of the CYGNSS microsatellites to be launched simultaneously in pairs. Credit: NASA

CYGNSS Deployment Module

http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwjow83xqt3OAhUB4GMKHQXCABYQjRwIBw&url=http://www.nasa.gov/cygnss/the-science-of-cygnss&psig=AFQjCNHfeUToAxMaQKpLUPQBTKudqO7UKg&ust=1472240629190895

Space Systems





Features

Scalable deployment module based on existing design Complete satellite deployment solution

Enables two satellites to be launched at same time Customizable separation rates

Low-shock, debris-free separation Heritage mechanisms

Heritage minimizes nonrecurring engineering (NRE) Options for photos/videos of spacecraft separation

Integrated DMAU, cabling/harnessing

Applications

Spacecraft launch and separation

Heritage Programs

Cyclone Global Navigation Satellite System (CYGNSS)


U.S. SI

Mechanical

Envelope dimensions 18 in x 48 in 46 cm x 121 cm

Deployment module system mass 97 lb 44 kg

Max quasi static accelerations (worst-case loading from sine burst testing)

11.0 g (X), 2.53 g (Y), 5.75 g (Z).

Number of satellites / Mass per satellite 8 x 29 kg per spacecraft

Satellite separation velocity 0.65 meters per second

Satellite tip-off rate ≤ 7°/s

Source shock < 400 g

Random vibe Based on the CYGNSS random vibration, spectrum was notched to give the following test levels: 2.27 grms (X), 3.27 grms (Y), 2.82 grms (Z)

Release time 15 to 155 msec (over operational environment conditions)

Simultaneity Deploys two (2) opposing spacecraft simultaneously within 100 ms of each other

Electrical

HDRM power input (per device) Typical: 45 W @ 3.5 A @ 20 °C

HDRM release signal range for operating temperatures

Typical: 3.5 A, 35 msec @ 20 °C

Range: 2.3 A to 7 A, 15 msec to160 msec

HDRM shape memory alloy (SMA) resistance (single circuit)

3.9 ± 0.1 Ω @ 20 °C

HDRM no-fire current 0.25 A min.

HDRM all-fire current (200 msec) 2.3 A

Thermal




Space Systems





QwkSep® 15 Low-Profile Separation System (LPSS)

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems QwkSep 15 Low-Profile Separation System (LPSS) provides a low-shock solution to small satellite separation in an extremely low profile. The system is designed for a standard EELV Secondary Payload Adapter (ESPA) with a 15-inch satellite interface launch configuration (orthogonal to thrust axis). The interface rings have integrated adjustable kick off springs, pass-through separation connectors and redundant telemetry indication of positive separation. The system is released with a mini, low-shock Clamp Band Opening Device (CBOD). This design configuration has heritage in more than 100 successful flight releases.

The CBOD features redundant circuits driven by a typical pyrotechnic firing pulse. Based on our space-qualified Fast-Acting Shockless Separation Nut (FASSN) technology, the CBOD restrains the band tension bolts with a double helix, flywheel nut. The back drive torque of the high lead, band tension bolts is reacted through the CBOD by the latched flywheel nut. A pyro-compatible pulse releases the flywheel nut, which spins up and ejects the tension bolts. The strain energy in the band is converted to rotational energy in the flywheel nut allowing the two mating halves to separate with extremely low shock.

Features

Ultra-high reliability payload separation Redundant electrical trigger circuits

>25% stiffer and >40% more load capability than comparable, alternative solutions

Utilizes heritage release technology of CBOD with redundant NASA standard initiator-driven pin puller

Low-shock operation Scalable between 12-inch and 24-inch sizes

Designed for full ESPA payload weight and ESPA dynamic environments

Optional nonpyrotechnic mini-CBOD release mechanism available for extremely low-shock release

Straightforward integration and operation No generated debris

Resettable for multiple ground operations Based on extensive clamp band heritage

Dimensions


QwkSep 15 Low-Shock Clamp Band. The QwkSep 15 clamp band system provides a small satellite separation solution.

Space Systems





Applications

Auxiliary payload separation ESPA-compatible integration and operation

Heritage Programs

Nanosat Orbital Express

Atlas V* Delta IV*

Arianne* Sea Launch*

Proton* Falcon 9*

*Note: Larger diameter version (primarily 47-inch and 66-inch systems); have more than 100 combined flight releases on these LVs.


U.S. SI

Mechanical

Payload capability 400 lbm with 20-inch center of gravity (CG)

Offset height above ESPA interface

181 kg (508 mm CG height)

Quasi-static environment 8.5 g axial and lateral dynamic loading simultaneously

Random vibration environment Qualified to NASA General Environmental Verification Specification (GEVS) levels for large (400+lbm) payloads (5.6 grms)

Stiffness Axial:

Moment:

2.15E6 lb/in

9.62E7 in•lb/rad

3.76E4 N/m

1.09E7 N•m/rad

Envelope dimensions Ø15 BCD x 2.1-inch max. stack height Ø381 BCD x 53.3 mm

Mass, full system (not including fasteners, harness)

15 lbm max. 6.8 kg max.

Mass, flyaway 4.0 lbm max. 1.8 kg max.

Life (as-delivered) 12 full-load release cycles


Source shock Pyro: 1,000 g from 1 kHz to 2 kHz near actuator

Non-pyro option: 100 g max. from 10 Hz to 10 kHz

Tip-off rate 0.5 °/s max.

Kick-off rate (separation velocity) 1 ft/s min. 0.3 m/s min.

Electrical

Release signal Pyro: NASA Standard Initiator (NSI)-firing pulse

Non-pyro option: 3.5 amps for 50 ms (typical)

Separation telemetry Redundant loop-back circuits indicate positive separation

Release time 50 ms max.

Thermal

Operating temperature range Pyro: -90 °F to +219 °F

Non-pyro option: -85 °F to +167 °F

Reset

Refurbishment Replace standard NSI-Pin Puller trigger

Special tools SNC band loading tool; SNC spring compression tools

Time required for reset ~ 2 hours


Space Systems





QwkSep® 24 Low-Profile Separation System (LPSS)

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems QwkSep 24 Low-Profile Separation System (LPSS) provides a low-shock solution to small satellite separation in an extremely low profile. The system is designed for standard ESPA-Grande (EELV Secondary Payload Adapter) with a 24-inch satellite interface launch configurations (orthogonal to thrust axis). The interface rings have integrated adjustable kick off springs, pass-through separation connectors and redundant telemetry indication of positive separation. The system is released with a mini, low-shock Clamp Band Opening Device (CBOD). This design configuration has heritage in more than 100 successful flight releases.

The CBOD features redundant circuits driven by a typical pyrotechnic firing pulse. Based on our space-qualified Fast-Acting Shockless Separation Nut (FASSN) technology, the CBOD restrains the band tension bolts with a double helix, flywheel nut. The back drive torque of the high lead, band tension bolts is reacted through the CBOD by the latched flywheel nut. A pyro-compatible pulse releases the flywheel nut, which spins up and ejects the tension bolts. The strain energy in the band is converted to rotational energy in the flywheel nut allowing the two mating halves to separate with extremely low shock.

Features

Ultra-high reliability payload separation Redundant electrical trigger circuits

>25% stiffer and >40% more load capability than comparable, alternative solutions

Utilizes heritage release technology of CBOD with redundant NASA standard initiator-driven pin puller

Low-shock operation Scalable between 12-inch and 24-inch sizes

Designed for full ESPA-grande payload weight and ESPA dynamic environments

Optional nonpyrotechnic mini-CBOD release mechanism available for extremely low-shock release

Straightforward integration and operation No generated debris

Resettable for multiple ground operations Based on extensive clamp band heritage

Dimensions


QwkSep 24 Low-Shock Clamp Band. QwkSep 24 clamp band provides a small satellite separation solution.

Space Systems





Applications

Auxiliary payload separation ESPA-compatible integration and operation

Heritage Programs

Nanosat Orbital Express

Atlas V* Delta IV*

Arianne* Sea Launch*

Proton* Falcon 9*

*Note: Larger diameter version (primarily 47-inch and 66-inch systems); have more than 100 combined flight releases on these LVs.


U.S. SI

Mechanical

Payload capability 660 lbm with 20-inch center of gravity (CG) Offset height above EELV Secondary

Payload Adapter (ESPA) interface

300 kg (508 mm CG height)

Quasi-static environment 8.5 g axial and lateral dynamic loading simultaneously

Random vibration environment Qualified to NASA General Environmental Verification Specification (GEVS) levels for large (400+lbm) payloads (5.6 grms)

Stiffness Axial:

Moment:

6.23E6 lb/in

4.45E8 lbin/rad

1.09E3 N/m

5.03E7 Nm/rad

Envelope dimensions Ø24 BCD x 2.1-inch max. stack height Ø610 BCD x 53.3 mm

Mass, full system (not including fasteners, harness)

21 lbm max. 9.5 kg max.

Mass, flyaway 5.0 lbm max. 2.3 kg max.

Life (as-delivered) 12 full-load release cycles


Source shock Pyro: 1,000 g from 1 kHz to 2 kHz near actuator

Non-pyro option: 100 g max. from 10 Hz to 10 kHz

Tip-off rate 0.5 °/s max.

Kick-off rate (separation velocity) 1 ft/s min. 0.3 m/s min.

Electrical

Release signal Pyro: NASA Standard Initiator (NSI)-firing pulse

Non-pyro option: 3.5 amps for 50 ms (typical)

Separation telemetry Redundant loop-back circuits indicate positive separation

Release time 50 ms max.

Thermal

Operating temperature range Pyro: -90 °F to +219 °F

Non-pyro option: -85 °F to +167 °F

Pyro: -68 °C to +104 °C

Non-pyro option: -65 °C to +75 °C

Reset

Refurbishment Replace standard NSI-Pin Puller trigger

Special tools SNC band loading tool; SNC spring compression tools

Time required for reset ~ 2 hours


Space Systems






Sierra Nevada Corporation’s (SNC) Space Systems is an industry leader in precision, low-disturbance pointing systems for space applications. We have developed a number of single- and dual-axis pointing systems for deploying and positioning antennae, solar array drives and mechanisms, optical telescopes, and instrument mechanisms. Each axis of the pointing system is typically driven by a precision rotary actuator, which features a redundant stepper motor, harmonic drive and/or hybrid transmission, with various position telemetry options. The rotary actuator is configurable with multiple options, through holes for cable management, slip rings, twist capsules, RF Rotary joints, telemetry sensors and adjustable hard stops. The biaxial brackets have been designed for minimal orthogonal distortion, high stiffness and low mass. SNC pointing systems are qualified and flight proven with NASA programs, commercial and military satellites and the International Space Station.

Although we specialize in custom-engineered open- and closed-loop solutions, our list of qualified motors, actuators, gimbals, and drive electronics has grown into a substantial portfolio that is capable of supporting a wide range of applications and sizes with minimal nonrecurring effort required.

Catalog data sheets for the Sierra Nevada Corporation’s Pointing Systems and Motion Control technology area include:

C14 Bi-Axis Gimbal

C14 Incremental Rotary Actuator

C14-750 W Solar Array Drive Assembly



CEH25 Compact Incremental Rotary Actuator, 3-Phase

DM45L Gearmotor

EH25 Bi-Axis Gimbal, 3-Phase

EH25 Incremental Rotary Actuator, 3-Phase

Electronic Control Unit (ECU)

eMotor

HT32 Gearmotor

HT45S Gearmotor with Brake

H25 Bi-Axis Gimbal, 4-Phase

LDC20 Low-Disturbance Gimbal

Lightweight 2-Axis Mini Gimbal

LT32 Gearmotor

LT45L Gearmotor

Space Systems





LT45S Gearmotor with Brake

M45L Motor

M45S Motor

Rotary Drive Electronics (RDE)

Simple Stepper Driver (SSD)

Size 23 Incremental Rotary Actuator

T25 Incremental Rotary Actuator

Universal Microstepping Control Driver (UMCD)

Space Systems

C14 Bi-Axis Gimbal




C14 Bi-Axis Gimbal

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems offers a lightweight, bi-axial gimbal, featuring the C14 incremental rotary actuator developed specifically for critical spacecraft pointing applications. Originally developed for antenna pointing mechanisms on communications satellites, the device has also been adapted for solar array drives and is suitable for thruster or instrument pointing.

The actuator uses a 2-phase permanent magnet stepper motor to drive a zero backlash harmonic drive. An optional 3-phase motor is also available. Magnetic modeling and optimization ensure the permanent magnet stepper motor takes full advantage of the available volume for maximum performance per unit weight. Redundant versions are fully isolated with Nomex-Kapton insulators to prevent failure propagation. High capacity 440C stainless steel ball bearings support the output shaft for maximum stiffness and life. The actuator’s titanium construction ensures high strength and consistent performance over a broad temperature range.

A high-stiffness, stainless steel harmonic drive with modified tooth profile and circular spline provides outstanding stiffness and torque capability with extremely low weight. A custom Oldham coupling between the motor assembly and transmission allows for a large through hole that can be used for wire routing, RF rotary joints, or waveguides. The motor and transmission are designed as freestanding units that allow for modular combinations of motors and transmissions to easily adapt the assembly to a variety of applications.

The gimbal features an aluminum biaxial bracket that has been optimized for low mass and high stiffness. A black anodized, high-emissivity surface finish promotes thermal management, while the low-resistance conversion coating at the mating surfaces ensures electrical bonding throughout the gimbal.

Dimensions


C14 Bi-Axis Gimbal

Space Systems

C14 Bi-Axis Gimbal




Features

Compact design and mass efficient configuration Potentiometer for position telemetry

2-phase, 3-phase or 4-phase motor windings High stiffness and load capacity in a small package

Electrical redundancy available Internal heaters and thermistor

Bray or Pennzane lubrication Multiple harmonic drive ratios and optional hard stops

Note: Optional: Launch locks, RF coaxial cables, RF joints, and integrated antennas available upon request

Applications

Critical spacecraft pointing applications Solar array drive, antenna, thruster, or instrument pointing

Heritage Programs

Eagle Geosynchronous Space Situational Awareness Program (GSSAP) 1, 2, 3, and 4

OrbView -3 & -4 Samaritan


U.S. SI

Mechanical

Mass 2.7 lbm, excluding cables

~3.25 lb including 33 inches of cabling

1.23 kg, excluding cables

~1.5 kg including 85 cm of cabling

Step size 0.0625

Slew rate >9°/s at no load

Max. output acceleration 6°/s2

Output torque @ 4°/s 125 in-lb typical at 77 °F 14 Nm

Maximum inertial load > 9 lb-in-s2 >1 kg-m2

Unpowered holding torque 8 in-lb 0.9 Nm

Actuator Torsional stiffness 30,000 in-lb/rad 3,390 Nm/rad

Actuator Independent Load Ratings (consult SNC engineering for combined loads)

Axial load capacity (maximum) 1,425 lb 6,338 N

Radial load capacity (maximum) 275 lb 1,223 N

Moment load capacity (maximum) 800 in-lb 90 Nm

Electrical

Winding resistance 57 Ω (nominal, 2-phase)

Winding inductance 30 mH typical

Torque constant 0.636 Nm/A

Heater power 10 W (nominal, each)

Potentiometer linearity 0.25% over 350° (357° total electrical range)

Qualified Thermal Environment

Operating temperatures -94 °F to 158 °F -70 °C to 70 °C

Nonoperating temperatures -139 °F to 185 °F -95 °C to 85 °C


Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems offers a lightweight, incremental rotary actuator developed specifically for critical spacecraft pointing applications. Originally developed for antenna pointing mechanisms on communications satellites, the device has also been adapted for solar array drives and is suitable for thruster or instrument pointing as well.

The actuator uses a 2-phase, permanent magnet stepper motor to drive a zero-backlash harmonic drive. An optional 3-phase motor is also available. Magnetic modeling and optimization ensure the permanent magnet stepper motor takes full advantage of the available volume for maximum performance per unit weight. Redundant versions are fully isolated with Nomex-Kapton insulators to prevent failure propagation. High-capacity 440C stainless steel ball bearings support the output shaft for maximum stiffness and life. The actuator’s titanium construction ensures high strength and consistent performance over a broad temperature range.

A high-stiffness, stainless steel harmonic drive with modified tooth profile and circular spline, provide outstanding stiffness and torque capability with extremely low weight. A custom Oldham coupling between the motor assembly and transmission allows for a large through-hole that can be used for wire routing, RF rotary joints, or waveguides. The motor and transmission are designed as freestanding units that allow for modular combinations of motors and transmissions to easily adapt the assembly to a variety of applications.

Features

Compact design, volume, and mass efficient configuration Light-weight, all-titanium construction

High-performance, 2-phase motor windings 440C stainless steel harmonic drive/ABEC 7 ball bearings

3-phase or 4-phase winding configurations available High stiffness and load capacity in a small package

Potentiometer for position telemetry Electrical redundancy available

Internal heaters and thermistor Multiple harmonic ratios and optional hard stops available

Dimensions


C14 Rotary Actuator

Space Systems





Applications

Antenna pointing mechanisms Camera pointing mechanisms

Deployment systems Thruster gimbal applications

Heritage Programs

OrbView-3 & -4 Geosynchronous Space Situational Awareness Program (GSSAP) 1, 2, 3, and 4

Samaritan


U.S. SI

Mechanical

Mass 1.25 lb 0.57 kg

Step size 0.0625°

Slew rate >9 °/s @ no load

Output torque @ 4 °/s 125 in-lb typical @ 77 °F 14 Nm typical @ 25 °C

Unpowered holding torque 8 in-lb min. 0.9 N•m min.

Torsional stiffness 30,000 in-lb/rad 3,390 N•m /rad

Electrical

Winding resistance 57 Ω (nominal, 2 phase)

Winding inductance 30 mH typical

Torque constant 0.636 N•m /A


Independent Load Ratings (Consult SNC engineering for combined loads)

Axial load capacity 1,425 lb 6.3 kN

Radial load capacity 275 lb 1.2 kN

Moment load capacity 800 in-lb 90 N•m

Qualified Thermal Environment




Space Systems

C14–750 W Solar Array Drive Assembly





Design Description

Sierra Nevada Corporation’s (SNC) Space Systems offers a lightweight, incremental Solar Array Drive Assembly (SADA) developed specifically for spacecraft solar array deployment and pointing applications. The C14-750 W SADA is derived from an actuator that has many years of flight heritage and a slip ring assembly that has been used on multiple spacecraft as well.

The actuator uses a 2-phase permanent magnet stepper motor to drive a zero backlash harmonic drive. An optional 3-phase motor is also available. Magnetic modeling and optimization ensure the permanent magnet stepper motor takes full advantage of the available volume for maximum performance per unit weight. Redundant versions are fully isolated with Nomex-Kapton insulators to prevent failure propagation. High capacity 440C stainless steel ball bearings support the output shaft for maximum stiffness and life. The actuator’s all-titanium construction ensures high strength and consistent performance over a wide temperature range.

A high stiffness, stainless steel harmonic drive with modified tooth profile and circular spline provide outstanding stiffness and torque capability with extremely low weight. A custom Oldham coupling between the motor assembly and transmission allows for a large through hole that can be used for wire routing, RF rotary joints, or waveguides. The motor and transmission are designed as freestanding units that allow for modular combinations of motors and transmissions to easily adapt the assembly to a variety of applications. The slip ring assembly is built in the USA in accordance with SNC specifications. The slip ring is a monofilament gold-on-gold design with many years of successful flight heritage. Each ring is contacted by four brushes and has 2A capacity after derating for vacuum operation.

Features

Compact design, volume-, and mass-efficient configuration

Lightweight, all-titanium construction

High performance, 2-phase motor windings 440C stainless steel harmonic drive / ABEC 7 ball bearings

3-phase or 4-phase winding configurations available High stiffness and load capacity in a small package

Potentiometer for position telemetry Electrical redundancy available

Dimensions


C14-750 W Solar Array Drive Assembly with Slip Rings

Space Systems





Applications

Solar Array Drives

Heritage Programs

OrbView-3 & -4 (actuator) Geosynchronous Space Situational Awareness Program (GSSAP) 1, 2, 3, and 4 (actuator)

Multiple restricted satellite programs (slip rings) STPSat-5

Samaritan (actuator) Gladiator


U.S. SI

Mechanical

Mass 2.3 lb excluding cables

~3.5 lb with 40” cables

1.05 kg excluding cables

~1.6 kg with 1 m cables

Step size 0.0625°

Slew rate >9 °/s @ no load

Output torque @ 4 °/s 125 in-lb typical @ 77 °F 14 N-m typical @ 25 °C

Unpowered holding torque 8 in-lb min. 0.9 N-m min.

Torsional stiffness 20,000 In-lb/rad 2,260 N-m/rad

Electrical

Slip ring capacity 30 transfers, each derated to 2 A

Motor winding resistance 57 Ω (nominal, 2 phase)

Motor winding inductance 30 mH typical

Motor torque constant 0.636 Nm/A


Independent Load Ratings (consult SNC engineering for combined loads)

Axial load capacity 2,300 lb 10.2 kN

Radial load capacity 290 lb 1.3 kN

Moment load capacity 800 in-lb 90 Nm

Thermal Environment




Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems, in support of Earth observation satellites, has designed, developed, and delivered an Antenna Pointing Mechanism (APM) utilizing the C20 Incremental Rotary Actuators (RA) for its axis drives. The C20 RAs are very low disturbance actuators, ideal for low jitter, high-resolution applications in an open-loop stepper motor driven system.

SNC’s C20 unit is composed of a 3-phase, bipolar, 15-degree stepper motor with redundant windings that are insulated from one another to prevent failure propagation. The motor is directly coupled to a 50:1 harmonic drive gear reducer that features maximum stiffness, strength, and zero backlash. Output position feedback is provided by integral redundant potentiometers with absolute accuracy to ±0.1 percent over electrical travel. A single-channel RF rotary joint, redundant heaters and thermistors, and internal hard stops complement the actuators’ operational features.

A space-qualified twist capsule is available to carry signal and power currents through the actuator, simplifying wiring in the assembly and negating wire stress concentrations caused by actuator or gimbal motion. The RF joints carry RF signals through the actuators’ axis of rotation; the RF cabling routes the RF signal through the actuator to the spacecraft antenna.

Features

A low-torque disturbance, 3-phase 15-deg stepper motor Redundant heaters and thermistors

Redundant stator windings Redundant output position potentiometers

50:1 no-backlash, high stiffness, harmonic drive gear set RF rotary joint and internal hard stops are available

Dimensions



Space Systems





Applications

Antenna Pointing Mechanisms Gimbals

Heritage Programs

GeoEye-1


U.S. SI

Mechanical

Actuator size (OD x L) Ø4.0 in x 4.5 in Ø101.6 mm x 114.3 mm

Actuator weight 4.1 lb 1.86 kg

Through hole ID Ø.375 in Ø9.5 mm

Step size 0.3°, .007° with microstepper control

Electrical

Motor type 3-phase, wye-connected, redundant, 15° stepper

Voltage, nominal 28 Vdc

Resistance (at ambient temperature) 22.6 Ω

Driver type Microstepper with current control

Potentiometer resistance 5k Ω ± 5%

Potentiometer electrical travel 200° min. on each resistive track

Potentiometer linearity ± 0.1% over electrical travel

Thermal

Heater resistance 78 Ω ± 2% (each heater)

Temperature, operating -13 °F to +149 °F -25 °C to +65 °C

Temperature, survival -130 °F to 176 °F -90 °C to +80 °C


Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems has designed and developed a new, robust C50 rotary actuator for spaceflight and satellite applications. Featuring a 6-degree stepper motor, 100:1 C50 harmonic drive gear reducer, motor and output resolvers in a stiff, high load capacity package, the actuator combines relatively high output slew rates, accuracy, and torque margin.

The C50 Actuator features a 3-phase, wye connected, 6-degree stepper motor with redundant windings that are fully isolated to prevent failure propagation. The 20-pole motor has minimal cyclic torque for ultra-smooth actuation. A nonredundant incremental motor resolver accurately tracks motor position to ±0.4° for testing feedback or possible commutation.

The 100:1 C50 harmonic drive unit is fabricated from corrosion-resistant stainless steel, which is heat-treated for strength and manufacturability. Its torque rating is 3,328 in-lb at 200 rpm with a torsional stiffness of approximately 1.8 x 106 in-lb/rad. Oversized 440C stainless steel ABEC 7 ball bearings in a DB configuration support the output shaft for maximum stiffness and life. The space-rated lubricant is Nye oil 2001 with 3 percent PbNp.

The nominal output slew rate is 2.7 degree/second at a motor pulse rate of 45 pps. Running torque is typically 1,000 in-lb; unpowered holding torque is greater than 250 in-lb. Redundant coarse variable reluctance resolvers provide output telemetry to within ±0.1°.

Features

3-phase, redundantly wound, 6-degree stepper motor Spaced-rated lubricant: Nye 2001-3 PbNp

100:1 C50 harmonic drive reducer High torsional and moment output stiffness

Motor resolver feedback to ±0.4° at motor shaft Output resolver telemetry to ±0.1°

Dimensions



Space Systems





Applications

High Torque, Precision Actuation

Heritage Programs

Restricted program


U.S. SI

Mechanical

Size (OD x L), including connector boss Ø8.0 in x 13 in Ø203.2 mm x 330.2 mm

Weight 40.0 lb 18.2 kg

Torsional stiffness 1,200,000 in-lb/rad, min. 135,600 N-m/rad

Qual-level random vibration 24.7 grms (Y axis) ; 20.4 grms (X-Z axes)

Electrical

Motor type 3-phase, wye-wound, redundant, 6-degree stepper motor

Voltage, minimum 20 Vdc

Resistance (room temperature) 1.7 Ω ± 5%

Output resolver input 4 Vrms ± 10%, 5 kHz ± 10%

Thermal

Temperature, operational 32 °F to 140 °F 0 °C to +60 °C

Temperature, survival -24.8 °F to 175.2 °F -31 °C to +74 °C


Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems brings a long history of manufacturing space-qualified motors and actuators, both in one-off and multiple unit production runs. The CEH25 Compact Incremental Rotary Actuator, 3-Phase, based on a heritage design which has been in continuous production for several years, utilizes flight-proven design, assembly, and test heritage. SNC maintains an inventory of CEH25 long-lead parts in stock.

The CEH25 compact gimbal features an advanced hybrid transmission, consisting of a planetary gearbox manufactured to fit completely within a high-stiffness, zero-backlash harmonic drive. The combined transmission provides high internal torque margins throughout the performance range, allowing reduction in the required motor size and resulting in a significantly lighter actuator with exceptional output capability.

The CEH25 rotary actuator (RA) features a lower profile 28 Vdc, 3-phase, permanent magnet, 1.5-degree stepper motor with redundant windings that are insulated from one another to prevent failure propagation. Magnetic modeling and optimization ensures the stepper motor’s maximum performance per unit weight. Telemetry is provided by redundant potentiometers that use an SNC-proprietary process, yielding previously unattainable potentiometer life in a spaceflight environment. Redundant potentiometers monitor motor and output shaft position with sufficient accuracy to provide absolute position to within a single step over the full operating range. Oversized 440C stainless steel ABEC 7 ball bearings support the output shaft for maximum stiffness and life. The RA’s structural components are fabricated from lightweight high-stiffness titanium and high-strength aluminum alloys. Careful selection of materials and precision-machined components ensure consistent performance over a broad temperature range. The RA is capable of full 360-degree rotation with adjustable hard stops.

Features

High stiffness and load capacity High-powered and unpowered torque capability

Fine-pointing resolution, 0.00246° per step Long life, qualified for more than 1 million dithering cycles

200% minimum torque margin motor design Redundant, accurate, potentiometer telemetry

Internal heaters with temperature sensors & thermostats Space-qualified Pennzane or Bray lubricants

Motor available as 2-, 3-, or 4-phase stepper Extreme environmental capability

Low power consumption Full rotation; field-adjustable, hard stop placement

Dimensions

Note: All dimensions are in inches.

CEH25 Compact Rotary Actuator, 3-Phase

Space Systems





Applications

Antenna pointing mechanisms Deployment mechanisms

Camera pointing mechanisms Robotics applications

Solar array drives

Heritage Programs

ViaSat (Oct 2011) Asia Broadcast Satellite (ABS-2)

EchoStar XVI & XVII (Nov 2012) AsiaSat-6

EutelSat 25B Intelsat ISDLA-1 & -2

DirecTV (DTV-14) National Broadband Network (NBN) Company 1A & 1B

Thor-7 StarOne C4

Parker Solar Probe Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx)


U.S. SI

Mechanical

Envelope dimensions 5.4 in x Ø4.8 in 137 mm x Ø121 mm

Mass (including potentiometers, heaters, thermostats, and hard stops)

4.5 lb 2.0 kg

Unpowered holding torque >250 in-lb >28 N•m

Gear ratio 610:1

Output resolution .00246°

Life 15 x 1.5 years (>29 million motor steps)

Electrical

Motor type 3-phase, wye-wound, redundant, 1.5° stepper


Resistance 20 Ω

Power, nominal 8.3 W

Fine potentiometer (redundant) 350° electrical travel, 10 kΩ

Coarse potentiometer (redundant) 350° electrical travel, 10 kΩ

Sensor, temperature Platinum RTD 2,000 Ω @ 0 °C

Thermal



Heater resistance 98 Ω ± 5% (each heater); thermostat controlled


Space Systems

DM45L Gearmotor




……..

DM45L Gearmotor

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems, in support of missions to Mars, has designed, tested, and delivered a unique dual-mode planetary gearmotor. DM45L includes two output shaft splines operated at to two different gear ratios to allow the user to select either a high speed or high torque option. Qualified for use in a percussive drill device, this unit is capable of operating throughout a functional vibration environment.

This distinctive gearmotor utilizes SNC’s own M45L motor and transmits torque simultaneously through both 2-stage and 4-stage planetary geartrains to high strength output spline features. The gearbox includes high quality stainless steel gears (Q10), supported by 440C ball bearings and silicon nitride roller bearings. The gearmotor is capable of operation and qualified for life at temperatures as low as -70°C. The DM45L gearmotor incorporates space-rated lubricant Brayco 815Z oil and Braycote 600EF grease.

Features

3-phase brushless DC motor operation High strength output spline features

High speed (350 rpm) and high torque (560 in-lbf) outputs Qualified for operation in functional vibration environment

32:1 and 507:1 gear ratios Broad Operation and Non-Operational temperature range

Dimensions


DM45L Gearmotor

Space Systems

DM45L Gearmotor




Applications

Robotics applications High speed & high torque applications

High vibration applications Drill mechanisms

Heritage Programs

Mars 2020 Mars Science Laboratory (gearbox)

Product Specifications DM45L (High Torque Output) DM45L (High Speed Output)

U.S. SI U.S. SI

Mechanical

Gear Ratio 506.67:1 31.67:1

Envelope dimensions Ø 2.95 in x

6.02 in

Ø 75 mm x

153 mm

Ø 2.95 in x

6.02 in

Ø 75 mm x

153 mm

Mass, less cables < 4.38 lb < 2.0 kg < 4.38 lb < 2.0 kg

Operating Torque Contact Engineering Contact Engineering

Maximum Torque 668.2 in-lbf 64 Nm 62 in-lbf 7 Nm

No Load Speed, max 21.9 rpm 350 rpm

Unpowered Holding Torque, min N/A N/A N/A N/A

Torsional Stiffness, typ 7,740 in-lbf/rad 875 Nm/rad 1,742 in-lbf/rad 197 Nm/rad

Backlash, typ 6 mrad 53 mrad

Lubrication Brayco 815Z & Braycote 600EF Brayco 815Z & Braycote 600EF

Life (2X Margin) > 1,200 revs > 244,000 revs

Electrical

Motor Type 3-phase SNC M45L Brushless DC

Voltage, nominal (range) 26.9 VDC (15.3-31.5 VDC)

Winding Resistance 0.27 Ω

Winding Inductance 0.24 mH

Motor Driver 3-phase

Environmental

Operating & Qualified temperature -94°F to +158°F -70°C to +70°C -94°F to +158°F -70°C to +70°C

Non-Operating temperature -211°F to +257°F -135°C to +125°C -211°F to +257°F -135°C to +125°C

Random Vibration 10 grms

Pyrotechnic Shock 1,000 g @ 3,500 Hz


Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems has developed an Enhanced Hybrid (EH25) Bi-Axis Gimbal that has improved stiffness and torque capability closely modeled after our standard H25 gimbal. The EH25 Gimbal features very fine pointing resolution, position telemetry precise to within a single step, infinitely adjustable hard stops, internal heaters and temperature sensors, and extremely long-life capability.

The gimbal actuator features an innovative hybrid transmission consisting of a planetary gearbox designed to fit completely within a high stiffness, zero backlash harmonic drive. The combined transmission provides high internal torque margins throughout the operational range and enables enhanced performance.

Telemetry is provided by redundant potentiometers that use an SNC proprietary process, yielding previously unattainable potentiometer life in a spaceflight environment. Redundant potentiometers monitor motor and output shaft position with sufficient accuracy to resolve position within a single step over the full operating range.

SNC fabricates the gimbal structural components from lightweight high stiffness titanium and high strength aluminum alloys. Careful selection of materials and use of precision-machined components ensure consistent performance over a broad temperature range. Oversized 440C stainless steel ABEC 7 ball bearings support the output shaft for maximum stiffness and life. The gimbal actuators are capable of full 360-degree rotation and adjustable hard stops are available to limit gimbal travel to any customer requirement.

Features


Fine-pointing resolution, 0.0025° per step Long life, qualified for more than 1 million dithering cycles


Internal heaters with temperature sensors Space-qualified Pennzane lubricant



Dimensions


EH25 Bi-Axis Antenna Gimbal, 3-Phase

Space Systems





Applications

Antenna Pointing Mechanism with very fine pointing resolution

Gimbals

Heritage Programs





Thor-7 StarOne C4


U.S. SI

Mechanical

Envelope dimensions 11.2 in x Ø5.8 in 284.5 mm x Ø147 mm

Mass (excluding stops) 12.8 lb 5.8 kg

Unpowered holding torque > 400 inlb > 45 Nm

Torsional stiffness of two-axis gimbal 150,000 in-lb/rad, min. 17,000 N-m/rad, min.

Load inertia 2,655 lbf-in-sec2 300 kg-m2

Gear ratio 610:1

Output resolution (step) < .0025 °

Life 15 x 1.5 years (tested > 29 million motor steps)

Electrical

Motor type 3-phase, wye wound, redundant, 1.5-deg stepper motor


Resistance 117 Ω

Power, nominal 6.7 W

Fine Potentiometer (redundant) 350-deg electrical travel, 10 kΩ

Coarse potentiometer (redundant) 160-deg electrical travel, 8 kΩ

Sensor, temperature Platinum RTD, 2,000 Ω @ 0 °C

Thermal Qualification





Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems brings a long history of manufacturing space-qualified motors and actuators, both in one-off and multiple unit production runs. The Enhanced Hybrid (EH25) Incremental Rotary Actuator (RA), in continuous production for several years, utilizes flight-proven design, assembly, and test heritage. SNC maintains an inventory of EH25 long-lead parts in stock.

The EH25 Incremental Gimbal RA features an advanced hybrid transmission, consisting of a planetary gearbox manufactured to fit completely within a high-stiffness, zero-backlash harmonic drive. The combined transmission provides high internal torque margins throughout the performance range, allowing reduction in the required motor size and resulting in a significantly lighter actuator with exceptional output capability.

The RA features a 28 Vdc, 3-phase, permanent magnet, 1.5-degree stepper motor with redundant windings that are insulated from one another to prevent failure propagation. Magnetic modeling and optimization ensures the stepper motor’s maximum performance per unit weight. Telemetry is provided by redundant potentiometers that use an SNC-proprietary process, yielding previously unattainable potentiometer life in a spaceflight environment. Redundant potentiometers monitor motor and output shaft position with sufficient accuracy to provide absolute position to within a single step over the full operating range. Oversized 440C stainless steel ABEC 7 ball bearings support the output shaft for maximum stiffness and life. The RA’s structural components are fabricated from lightweight high-stiffness titanium and high-strength aluminum alloys. Careful selection of materials and precision-machined components ensure consistent performance over a broad temperature range. The RA is capable of full 360-degree rotation and adjustable hard stops are available to limit travel to any customer requirement.

Features


Fine-pointing resolution from 0.0025° to 0.0082° per step Long life, qualified for more than 1 million dithering cycles


Internal heaters with temperature sensors Space-qualified Bray or Pennzane lubricants



Dimensions


EH25 Incremental Rotary Actuator

Space Systems





Applications

Antenna pointing mechanisms Deployment mechanisms


Solar array drives

Heritage Programs





Thor-7 StarOne C4

Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS Rex)


U.S. SI

Mechanical

Envelope dimensions 5.0 in x Ø5.8 in 126 mm x Ø147 mm

Mass 5.8 lb 2.6 kg

Unpowered holding torque >400 in-lb >45 N•m

Gear ratio 610:1

Output resolution .0025° (or .0082°) per step

Life 15 x 1.5 years (>29 million motor steps)

Electrical

Motor type 3-phase, wye-wound, redundant, 1.5-deg stepper (or 5-deg stepper)


Resistance 70 Ω – 117 Ω

Power, nominal 6.7 W – 10 W

Fine potentiometer (redundant) 350-deg electrical travel, 10 kΩ

Coarse potentiometer (redundant) 160-deg electrical travel, 8 kΩ (or 350-deg electrical travel, 10 kΩ)


Thermal





Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems Electronic Control Unit (ECU) is a versatile stepper motor driver providing twelve channels of motor control (redundant six-channel motor drivers) with modes of micro or cardinal stepping as well as commandable current limit and acceleration control. Each control channel provides five analog inputs, typically motor current, board temperature, actuator temperature, and coarse and fine position data, which are digitized and available as telemetry on the serial data bus.

The ECU’s microstepping capability enables smooth motion for open-loop control of a stepper motor-driven mechanism. The finest microstep resolution available is automatically adjusted on the fly for each channel based on each motion command. The microstep resolution will be 8, 16, 32, or 64 microsteps per motor detent or cardinal step depending on step rate. The current limit can be commanded to any of eight preset values. Torque disturbances generated by stepper motor operation can be reduced by 1 to 3 orders of magnitude depending on the motor and actuator characteristics. SNC specializes in the optimization of motors, gearing, and drives for low-torque disturbance applications.

The ECU provides 3-phase bipolar stepper motor control. The unit can provide up to 2 amps of peak current on each channel and operates directly from spacecraft bus voltages of 22 Vdc to 36 Vdc. Current regulation maintains constant peak torque over full input voltage range and variations in motor resistance over temperature. The ECU uses SNC’s proprietary drive design to maximize motor performance in microstep mode.

Features

Optically coupled controller interface uses a low-voltage differential signaling (LVDS) physical layer

Each channel includes five analog health and status inputs that are digitized and delivered as telemetry over the serial data bus

Communication bus protocol allows commanding the following: Peak Current Limit, Microstepping On/Off, Acceleration On/Off, Powered Idle On/Off, System Reset, Cancel Step, Set Step Count, and Send Telemetry

Two independent controllers within the enclosure can be used independently or for primary/redundant operation. Each side contains three motor driver modules that can drive two separate motors each, resulting in a total of 12 motor drive channels

Dimensions



Space Systems





Applications

Antenna Pointing Solar Array Drives

Heritage Programs

Parker Solar Probe


U.S. SI

Mechanical


Mass 12.94 lb (TBC) 5.86 kg (TBC)

Electrical

Input operating voltage 22-36 Vdc

Power Dissipation (excluding pass thru power) ≤6 W Quiescent (One Side) (TBC)

Inrush current ≤1.5 A for 7.5 ms (TBC)

Power isolation ≥ 10 MΩ power to chassis ground (TBC)

Operation

Input commands Peak Current Limit, Microstep resolution, Acceleration On/Off, Powered Idle On/Off, System Reset, Cancel Step, Set Step Count, Telemetry position request

Differential Input Logic ‘1’ input threshold 100 mV ≤ Vd, assumes Vcm= +1.2V

Differential Input Logic ‘1’ input threshold -100 mV ≥ Vd, assumes Vcm = +1.2V

Step mode Cardinal stepping or microstepping

Resolution Microstepping: 8, 16, 32, or 64 μ-step / step (automatically selected))

Cardinal Step: 5 ms (200 steps/s) to 350 ms (2.86 steps/s)

Step rate Up to 200 cardinal steps per second

Number of phases 3-phase (bipolar, configurable)

Direction command sense Configurable, each channel via communications

Output current/channel Settable to 500, 600, 700, 800 mA peak current, per channel

Can extend range up to 2 A peak current, per channel upon customer request

Telemetry Motor current, Board temperature plus 3 analog input signals per control channel

Environmental

Operating temperature -13°F to +149 °F (TBC) -25 °C to +65 °C (TBC)

Nonoperating temperature -58 °F to +185 °F (TBC) -50 °C to + 85 °C (TBC)

Radiation 50 krad TID (SI) (TBC)

Vibration 28 g Random


Space Systems

eMotor




eMotor

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems eMotor is a high reliability alternative to brush motors. The eMotor uses integrated electronics to drive a brushless motor with only a dc input voltage.

The on-board electronics contain current limiting and active damping features, which are each configurable to specific applications. Direction of rotation is dependent on input voltage polarity. Total travel and speed measurement may be made from a 5 Vdc square-wave signal generated at 600 pulses per revolution. A high-precision, stainless steel, 3-stage planetary gearbox provides gear reduction.

The damping mode protects the electronics during over-speed conditions. The damping mode can also be commanded externally by shorting two connector pins; disconnecting the short turns the damper back into a motor again.

Initially designed to provide valve actuation on the ORION crew module, the eMotor can be configured to suit the customer’s requirements.

Features

Current limiting, configurable 600 pulse per revolution square wave output signal

22–34 Vdc nominal voltage Mil-Std-461 EMC compliant

Rad hard up to 100 krads Damping mode for over-speed control

Applications

Qualified for the Orion Program’s Environmental Control and Life Support System (ECLSS)

Space systems valve applications

A drop in, more reliable replacement for existing brush motors

Deployable and retractable systems

Dimensions


eMotor Brushless dc Motor with Gearhead

Space Systems

eMotor




Heritage Programs

Orion Environment Control and Life Support System


U.S. SI

Mechanical


Mass 17.5 oz 0.496 kg

Life cycles 10 launch per landing cycles

Operation time 2,500 hours, 4 rpm with 500 in-oz load, 99.9% reliability

Gear reduction 3-stage, 300:1 planetary gearbox

Lubrication Bray 815Z / 601EF

No load speed 9 rpm

Maximum torque Up to 900 in-oz Up to 6,355 mN-m

Unpowered holding torque 200 in-oz min. 1,412 mN-m min.

Electrical

Input voltage range 22–34 Vdc, reduced performance down to 12 Vdc

Max input current 500 mA

Electromagnetic interference Meets Mil-Std-461: CS101,114; RE101, RS103; CE101,102 (limit is shifted for CE102 +30 dB above 90 kHz)

Thermal

Operating temperatures -32.8 °F to +163 °F -36 °C to +73 °C



Space Systems

HT32 Gearmotor




HT32 Gearmotor

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems, in support of missions to Mars, has designed, tested, and delivered this high torque planetary gearmotor. The HT32 includes a 32mm motor with a magnetic detent wheel to increase holding torque capability, ideal for robotic applications that require locking/unlocking or reliable station keeping when unpowered.

This precision gearmotor utilizes a customized commercial M32 motor with two holding torque capability options and transmits torque through a 4-stage planetary geartrain to a high strength stainless steel output carrier, able to accommodate with multiple attachment features (integral 23T, 24DP gear shown). Gearboxes include high quality stainless steel gears (Q10), supported by 440C ball bearings and weight-efficient porous bronze bushings. The gearmotor is capable of operation and qualified for life at temperatures as low as -70°C. HT32 gearmotors incorporate space-rated lubricant Brayco 815Z oil and Braycote 600EF grease.

Features

3-phase brushless DC motor operation Output carrier attachment options

Magnetic detent wheel to increase holding torque High external load capability

Low backlash (<16 mrad) Broad Operation and Non-Operational temperature range

Dimension

Note: Dimensions above are in inches.

HT32-948 Gearmotor

Space Systems

HT32 Gearmotor




Applications

Robotics applications Slow speed applications

Deployment mechanisms Lock/Unlock mechanisms

Heritage Programs


Product Specifications HT32-948

U.S. SI

Mechanical

Gear Ratio 948.6:1


3.30 in

Ø 44 mm x

84 mm

Mass, less cables < 1.28 lb < 0.58 kg

Operating Torque Contact Engineering

Maximum Torque 182.5 in-lbf 20.6 Nm

No Load Speed, max 5.3 rpm

Unpowered Holding Torque, min 146 in-lbf 16.5 Nm

External Loads Contact Engineering

Torsional Stiffness, typ 94,200 in-lbf/rad 10,640 Nm/rad

Backlash, typ 8.0 mrad

Lubrication Brayco 815Z & Braycote 600EF

Life (2X Margin) >1,000 revs

Electrical

Motor Type

3-phase M32 Brushless DC with High-Torque Magnetic Detent Wheel

(Low-Torque Detent Optional)

Motor Holding Torque, nominal 2.83 in-oz

(1.42 in-oz)

20 mNm

(10 mNm)

Voltage, nominal (range) 28 VDC (12-28 VDC)

Winding Resistance 14 Ω


Environmental

Operating & Qualified temperature -94°F to +158°F -70°C to +70°C

Non-Operating temperature -211°F to +257°F -135°C to +125°C




Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems, in support of missions to Mars, has designed, tested, and delivered two variants of a high torque planetary gearmotor. Both include a 45mm motor with a solenoid brake to increase holding torque capability, ideal for robotic applications that require reliable station keeping when unpowered.

These high-capacity gearmotors utilize SNC’s own M45S motor brake and transmit torque through a 3-stage planetary geartrain to a high strength stainless steel output spline, which allows for straightforward integration at the next-higher level of assembly. Gearboxes include high quality stainless steel gears (Q10), supported by 440C ball bearings and weight-efficient porous bronze bushings. The gearmotors are capable of operation at temperatures as low as -70°C and are qualified for long-life with a minimum temperature of -55°C. HT45S gearmotors incorporate space-rated lubricant Brayco 815Z oil and Braycote 600EF grease.

Features

3-phase brushless DC motor operation Integral high-strength output shaft spline

Redundant brake coils for actuation Qualified for long life

81:1 and 178:1 gearbox options Broad Operation and Non-Operational temperature range

Dimensions

Note: All dimensions shown above apply to HT45S-178 and are in inches. HT45S-81 similar.

HT45S-178 Gearmotor with Brake (HT45S-81 not shown)

Space Systems





Applications

Robotics applications High torque applications

Deployment mechanisms

Heritage Programs


Product Specifications HT45S-81 HT45S-178

U.S. SI U.S. SI

Mechanical

Gear Ratio 81.19:1 178.34:1


4.30 in

Ø 65 mm x

109 mm

Ø 3.06 in x

4.65 in

Ø 77.6 mm x

118 mm



Maximum Torque 110.6 in-lbf 12.5 Nm 230.1 in-lbf 26.0 Nm

No Load Speed, max 87.7 rpm 39.9 rpm

Unpowered Holding Torque, min 101.8 in-lbf 11.5 Nm 262.9 in-lbf 29.7 Nm

Torsional Stiffness, typ 13,000 in-lbf/rad 1,470 Nm/rad 13,000 in-lbf/rad 1,470 Nm/rad

Backlash, typ 27.5 mrad 26.0 mrad


Life (2X Margin) 315,000 revs 203,000 revs

Electrical

Motor Type 3-phase SNC M45S Brushless DC with Solenoid Brake





Environmental

Operating temperature -94°F to +158°F -70°C to +70°C -94°F to +158°F -70°C to +70°C

Qualified life temperature range -67°F to +158°F -55°C to +70°C -67°F to +158°F -55°C to +70°C


Random Vibration 7.1 grms



Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems H25 Gimbal features very fine pointing resolution, position telemetry precise to within a single step, adjustable hard stops, and extremely long-life capability.

The gimbal actuator features a state-of-the-art hybrid transmission consisting of a planetary gearbox that is designed to fit completely within a high stiffness, zero backlash harmonic drive. The combined transmission provides high internal torque margins throughout the operational range and enables optimal performance.

Telemetry is provided by redundant potentiometers that have been treated using an SNC proprietary process, yielding previously unattainable potentiometer life in a spaceflight environment. Redundant potentiometers monitor motor and output shaft position with sufficient accuracy to resolve position within a single step over the full operating range.

The gimbal structural components are fabricated from lightweight high stiffness titanium and high strength aluminum alloys. Careful selection of materials and precision-machined components ensure consistent performance over a broad temperature range. Oversized 440C stainless steel ABEC 7 ball bearings support the output shaft for maximum stiffness and life. The gimbal actuators are capable of full 360-deg rotation and adjustable hard stops are available to limit gimbal travel to any customer requirement.

Features

High stiffness and load capacity Long life, qualified for more than 1 million dithering cycles

Fine pointing resolution, 0.003° per step Redundant, accurate, potentiometer telemetry

200% minimum torque margin motor design Space-qualified Pennzane lubricant

Motor available as 2- or 4-phase stepper Extreme environmental capability

Low power consumption Full rotation, removable hard stops

High powered and unpowered torque capability

Dimensions

Note: All dimensions above are in inches

H25 Bi-Axis Antenna Gimbal, 4-Phase

Space Systems





Applications

Antenna pointing mechanisms for very fine pointing resolution



Solar array drives

Heritage Programs

Clio Satellite Mobile User Objective System (MUOS-1–5)

Vietnam Satellite (Vinasat-1 and -2) Americom Communications Satellite (AMC-14)

EchoStar X PAN (USA-207)

Broadcasting Satellite System (BSAT-3C) Jabiru

Geostationary Operational Environmental Satellite R-Series (GOES-R)

Japanese Communications Satellites (JCSAT-9 through -12)

Space-Based Infrared System (SBIRS) Geosynchronous Earth Orbit (GEO)


U.S. SI

Mechanical

Envelope dimensions 11.6 in x Ø5.8 in 295 x Ø147 mm

Mass (excluding stops) 10.7 lb 4.9 kg

Unpowered holding torque > 650 in•lb > 70 N•m

Torsional stiffness of two-axis gimbal 100,000 in•lb/rad, min. 11,300 N•m/rad, min.

Load inertia 266,000 lbf-in-sec2 30,000 kg-m2

Gear ratio 1246.75:1

Output resolution (step) 0.003°

Life 15 x 1.5 years, 55,000 cycles, 775,000 motor revs

Electrical

Motor Type 4-phase, wye wound, redundant, 3.75-deg stepper


Resistance 323 Ω

Power, nominal 15 W

Fine potentiometer (redundant) 350-deg electrical travel, 10 kΩ

Coarse potentiometer (redundant) 350-deg electrical travel, 10 kΩ

Environmental Qualification



Random vibration 27 grms

Sine vibration 20 g


Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems has developed an innovative bi-axis gimbal that sets new standards for low-disturbance, open-loop operation when paired with one of our microstepping drives. The gimbal has completed qualification and is available for critical spaceflight applications.

This gimbal features advanced low-disturbance microstepping motors coupled to precision harmonic drives for high-efficiency operation. The actuators can be mounted in rotary isolators that further reduce the transmitted disturbance torque to extremely low levels.

The actuators feature permanent magnet stepper motors with redundant windings that are fully isolated from one another to prevent failure propagation. The unit can be provided in two- or three-phase motor configurations. Magnetic modeling and optimization ensures the permanent magnet stepper motor provides smooth motion.

Oversized 440C stainless steel ABEC 7 ball bearings support the actuator shafts for maximum stiffness and life. Telemetry is provided by redundant potentiometers that offer a low-cost, low-complexity solution to high-repeatability position measurement. The potentiometers provide absolute position telemetry, with resolution to within a single motor step. The gimbal is capable of ±99 deg rotation about the X- and Y-axis. The gimbal includes an integral launch lock mechanism that supports the gimbal and payload and uses a High Output Paraffin (HOP) Actuator to actuate the mechanism reliably and smoothly. The gimbal structural components and motor housings are fabricated from Aluminum alloys for their lightweight and good thermal conduction. Critical actuator components are fabricated from a Titanium alloy for added strength. Two RF channels transition the gimbal from top to bottom through RF rotary joints at the actuators. Electrical power and signals for the Y actuator transition the X-axis through a rotary twist capsule with 24 separate channels and a total power capacity of 15 W. This system, like all the mechanisms produced by SNC, is designed by engineering experts in the industry, who offer their strong customer support for their specific applications. Contact SNC for additional information.

Dimensions


LDC20 Low-Disturbance Torque Gimbal

Space Systems





Features

Two- or three-phase windings Redundant telemetry potentiometers or optical encoders

Movable hard stops Available radiation hardened microstepping motor driver

Bray or Pennzane lubrication Available with coax or waveguide rotary joints

Applications

Antenna and camera pointing mechanisms Robotics applications

Solar array drives Deployment mechanisms

Heritage Programs

GeoEye


U.S. SI

Mechanical

Mass 18 lbm 8.2 kg

Step Size at 64 microstep resolution 0.007°

Output Rotational Rate 8°/s

Powered Holding Torque 120 in-lb 13.6 Nm

Unpowered Holding Torque 3 in-lb 0.34 Nm

Torsional Stiffness 100,000 in-lb/rad 11,300 Nm/rad

Electrical


Dielectric Strength 500 Vdc

Insulation Resistance 100 M Ω

RF

Insertion Loss <1.5 dB

Frequency 8.025 – 8.4 Ghz

Power <10 W

VSWR Ratio <2.1:1

Thermal

Operating Temperatures -13 °F to 158 °F -25 °C to +70 °C

Nonoperating Temperatures -76 °F to 167 °F -60 °C to +75 °C


Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems Lightweight 2-Axis Mini Gimbal is a simple X/Y gimbal designed for spacecraft requiring a small, fast-moving antenna or other payload. The interface brackets and cable wrap spools are removable, providing excellent adaptability to many applications requiring a small gimbal with moderate pointing accuracy for 1- or 2-axis motion.

Each of the two axes uses identical actuators that can be used individually for a single-axis gimbal or coupled together with interface brackets to operate as a two-axis gimbal. Each actuator is outfitted with a nonredundant three-phase stepper motor, heater, temperature sensor, and potentiometer output position feedback.

The gimbal shown has a short interface bracket connecting it to the upper axis while the upper actuator bracket has an extended length in order to position the antenna higher above the deck. A high-flex coaxial cable with shape memory alloy (SMA) connectors is provided for antenna connections. The interface brackets and cable spools shown were sized to allow ±90° of rotation on each axis with continuous position telemetry and without self-interference.

Features

As little as 7.75-inches tall (8.4-inches tall as shown) when fully upright

Potentiometer accurate to ±0.5°, continuous over ±90

Maximum output speed 9°/s Actuator capable of continuous rotation

Output Cardinal Step Size 0.3° ±90° rotation on each axis, hard-stop limited

Gimbal mass of 3.5 lb as shown Minimum output torque 20 in-lb from -30 °C to +100 °C

Actuator mass of 1.3 lb without connectors or brackets Tested life of 60 k cycles

22–34 Vdc nominal voltage range

Dimensions



Space Systems





Applications

Spacecraft requiring a small, fast-moving antenna for moderate pointing accuracy; adaptable to many applications

Heritage Programs

Flight Unit Delivered to Customer

Product Specifications—Single Actuator

U.S. SI

Mechanical

Mass (without brackets or connectors) 1.3 lb 0.59 kg

Step size 0.3°±15%

Output torque 20–45 in-lb 2.25 to 5.08 Nm

Unpowered holding torque 60 in-oz min. 424 mN-m min.

Torsional stiffness 4,500 in-lb/rad nominal 508 N-m/rad nominal

Electrical

Voltage range 22 to 34 Vdc

Motor 3 Phase

Winding resistance 52 Ω nominal (L-2L)

Winding inductance 13 mH nominal (L-2L)

Potentiometer resistance 1,000 ±10% Ω

Thermal

Operating temperature -22 °F to 212 °F -30 °C to 100 °C

Nonoperating temperature -49 °F to 239 °F -45 °C to 115 °C

Heater resistance, single or dual configuration 112 Ω or 224 Ω 112 Ω or 224 Ω

Heater power, 28 V 7 W or 3.5 W 7 W or 3.5 W

Thermistor, S-310-P18 10,000 Ω @ 77 °F 10,000 Ω @ 25 °C


Product Specifications—Biax Gimbal with Coax Cable Spools

U.S. SI

Mechanical

Mass 3.5 lb 1.58 kg

Rotational stiffness, X axis (lower axis) 3,800 in-lb/rad nominal 430 N-m/rad nominal

Rotational stiffness, Y axis (upper axis) 4,425 in-lb/rad nominal 500 N-m/rad nominal

Electrical

Connectors, Motors Connector: Positronics PN: SDD15M00200G

Backshell: Glenair PN: 550T100M1R8B

Connector, Heaters and Telemetry Connector: Positronics PN: SDD26M00200G

Backshell: Glenair PN: 550T100M2R8B

Coax Cable Connectors Mil-C-39012 and Mil-Std-348

Thermal

Operating temperature -22 °F to 212 °F -30 °C to 100 °C

Nonoperating temperature -49 °F to 239 °F -45 °C to 115 °C


Space Systems

LT32 Gearmotor




LT32 Gearmotor

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems, in support of missions to Mars, has designed, tested, and delivered two variants of a low torque planetary gearmotor. Both include a 32mm motor with a magnetic detent wheel to increase holding torque capability, ideal for robotic applications that require reliable station keeping when unpowered.

These precision gearmotors utilize a customized commercial M32 motor with two holding torque capability options and transmit torque through a multi-stage planetary geartrain to a high strength stainless steel output carrier with multiple attachment features. This allows a single gearmotor design to drive multiple mechanisms. Gearboxes include high quality stainless steel gears (Q10), supported by 440C ball bearings and weight-efficient porous bronze bushings. The gearmotors are capable of operation at temperatures as low as -70°C and are qualified for long-life with a minimum temperature of -55°C. LT32 gearmotors incorporate space-rated lubricant Brayco 815Z oil and Braycote 600EF grease.

Features

3-phase brushless DC motor operation Multiple output carrier attachment features

Magnetic detent wheel to increase holding torque Qualified for long life

Low backlash (<16 mrad) High external load capability

30:1 and 169:1 gearbox options Broad Operation and Non-Operational temperature range

Dimensions

Note: All dimensions shown above apply to LT32-169 and are in inches. LT32-30 similar.

LT32 Gearmotors (LT32-30, Left; LT32-169, Right)

Space Systems

LT32 Gearmotor




Applications

Robotics applications Higher speed applications


Heritage Programs


Product Specifications LT32-30 LT32-169

U.S. SI U.S. SI

Mechanical

Gear Ratio 30.25:1 169.4:1


2.10 in

Ø 44 mm x

53 mm

Ø 1.72 in x

2.50 in

Ø 44 mm x

64 mm



Maximum Torque 15.9 in-lbf 1.8 Nm 69.0 in-lbf 7.8 Nm

No Load Speed, max 165.3 rpm 29.5 rpm

Unpowered Holding Torque, min 4.78 in-lbf 0.54 Nm 9.12 in-lbf 1.03 Nm

External Loads Contact Engineering Contact Engineering

Torsional Stiffness, typ 2,730 in-lbf/rad 308 Nm/rad 16,790 in-lbf/rad 1,897 Nm/rad

Backlash, typ 6.1 mrad 7.4 mrad


Life (2X Margin) 532,000 revs 24,300 revs

Electrical

Motor Type

3-phase M32 Brushless DC with High-Torque Magnetic Detent Wheel

(Low-Torque Detent Optional)

3-phase M32 Brushless DC with Low-Torque Magnetic Detent Wheel

(High-Torque Detent Optional)

Motor Holding Torque, nominal 2.83 in-oz

(1.42 in-oz)

20 mNm

(10 mNm)

1.42 in-oz

(2.83 in-oz)

10 mNm

(20 mNm)

Voltage, nominal (range) 28 VDC (12-28 VDC)



Environmental

Operating temperature -94°F to +158°F -70°C to +70°C -94°F to +158°F -70°C to +70°C

Qualified life temperature range -67°F to +158°F -55°C to +70°C -94°F to +158°F -70°C to +70°C





Space Systems

LT45L Gearmotor




……..

LT45L Gearmotor

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems, in support of missions to Mars, has designed, tested, and delivered a low torque, high speed planetary gearmotor. LT45L includes a 45mm motor, able to reach speeds over 10,000 rpm, ideal for high speed applications. Qualified for use in a percussion device, this unit is capable of operating throughout a functional vibration environment.

This robust gearmotor utilizes SNC’s own M45L motor and transmits torque through a single stage planetary geartrain to a high strength anodized titanium output. Gearboxes include high quality stainless steel gears (Q10), supported by 440C ball bearings. The gearmotor is capable of operation and qualified for life at temperatures as low as -70°C. The LT45L gearmotor incorporates space-rated lubricant Brayco 815Z oil and Braycote 600EF grease.

Features

3-phase brushless DC motor operation High-capacity output shaft tapped holes

High speed gearmotor (>3,400 rpm) Qualified for operation in functional vibration environment

3.43:1 gearbox Broad Operation and Non-Operational temperature range

Dimensions


LT45L-3 Gearmotor

Space Systems

LT45L Gearmotor




Applications

Robotics applications High speed applications

High vibration applications

Heritage Programs


Product Specifications LT45L-3

U.S. SI

Mechanical

Gear Ratio 3.43:1


3.74 in

Ø 64 mm x

95 mm



Maximum Torque 11.9 in-lbf 1.3 Nm

No Load Speed, max 3,230 rpm

Unpowered Holding Torque, min N/A N/A


Torsional Stiffness, typ 27.2 in-lbf/rad 3.1 Nm/rad



Life (2X Margin) >4,350,000 revs

Electrical

Motor Type SNC M45L Brushless DC Motor





Environmental






Space Systems





……..


Design Description

Sierra Nevada Corporation’s (SNC) Space Systems, in support of missions to Mars, has designed, tested, and delivered a low torque planetary gearmotor with high external load capacity. LT45S includes a 45mm motor with a solenoid brake to increase holding torque capability, ideal for robotic applications that require reliable station keeping when unpowered.

This highly capable gearmotor utilizes SNC’s own M45S motor brake and transmits torque through a 3-stage planetary geartrain to a high strength anodized titanium output carrier and is designed to withstand over 1,300 lbf (5,800 N) of reversing thrust load. Gearboxes include high quality stainless steel gears (Q10), supported by 440C ball bearings. The gearmotor is capable of operation and qualified for life at temperatures as low as -70°C. The LT45S gearmotor incorporates space-rated lubricant Brayco 815Z oil and Braycote 600EF grease.

Features

3-phase brushless DC motor operation High-capacity output shaft tapped holes

Redundant brake coils for actuation High external load capability

42.3:1 gearbox Broad Operation and Non-Operational temperature range

Dimensions


LT45S-42 Gearmotor

Space Systems





Applications

Robotics applications High load applications

Deployment mechanisms Lock/Unlock mechanisms

Heritage Programs


Product Specifications LT45S-42

U.S. SI

Mechanical

Gear Ratio 42.3:1


4.40 in

Ø 62 mm x

112 mm



Maximum Torque 56 in-lbf 6.3 Nm

No Load Speed, max 168.4 rpm

Unpowered Holding Torque, min 54 in-lbf 6.1 Nm


Torsional Stiffness, typ 54,500 in-lbf/rad 6,160 Nm/rad



Life (2X Margin) >50,000 revs

Electrical

Motor Type 3-phase SNC M45S Brushless DC with

Solenoid Brake





Environmental






Space Systems

M45L Motor




…

M45L Motor

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems, in support of missions to Mars, has designed, tested, and delivered a 45mm brushless DC motor optimized for high torque and high speed, robust enough to operate in a functional vibration environment.

These high output motors are central to the percussion drill mechanism of NASA Jet Propulsion Laboratory’s (JPL) Mars 2020 rover. Designed for low torque variation over temperature, the motor output torque, including viscous losses from lubrication, can be predicted to within ±10 mNm to across a temperature range from -70°C to +70°C. The motors are capable of operation and qualified for life at temperatures as low as -70°C. M45L motors incorporate space-rated lubricant Brayco 815Z oil and Braycote 600EF grease.

Features

3-phase brushless DC operation Qualified for long life (>50,000,000 revolutions with 2X margin)

Low winding resistance Broad Operation and Non-Operational temperature range

Robust mounting interface

Dimensions


M45L Motor

Space Systems

M45L Motor




Applications

Robotics applications High speed/torque applications

Planetary Gearmotor applications High vibration applications

Heritage Programs

Mars 2020

Product Specifications M45L

U.S. SI

Mechanical

Envelope Dimensions Ø 2.50 in x 2.76 in Ø 63.5 mm x 70.1 mm

Mass, less cables 1.1 lbs 0.48 kg

No Load Speed 11,075 rpm

Max Motor Torque, typ 56.6 in-oz 400 mNm

Holding Torque Type (Brake, Detent, etc) Detent

Life (2X Margin) 15,000,000

Electrical


Motor Kt, nominal 3.31 in-oz/A 23.4 mNm/A



Driver type 3-Phase


Environmental






Space Systems

M45S Motor




……..

M45S Motor

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems, in support of missions to Mars, has designed, tested, and delivered a 45mm brushless DC motor with a solenoid friction brake to increase holding torque capability, ideal for robotic applications that require reliable station keeping when unpowered.

These highly capable motors are the prime movers and brakes in each joint of the external robotic arm of NASA Jet Propulsion Laboratory’s (JPL) Mars 2020 rover. Designed to balance the demands of long life and low torque variation over temperature, the motor output torque, including viscous losses from lubrication, can be predicted to within ±10 mNm to across a temperature range from -70°C to +70°C. The motors are capable of operation at temperatures as low as -70°C and are qualified for long life missions with a minimum temperature of -55°C. M45S motors incorporate space-rated lubricant Brayco 815Z oil and Braycote 600EF grease.

Features

3-phase brushless DC operation Qualified for long life (>50,000,000 revolutions with 2X margin)

Redundant brake coils for actuation Broad Operation and Non-Operational temperature range

Robust mounting interface Low winding resistance

Dimensions


M45S Motor Brake

Space Systems

M45S Motor




Applications

Robotics applications Holding torque applications

Planetary Gearmotor applications

Heritage Programs

Mars 2020

Product Specifications M45S

U.S. SI

Mechanical

Envelope Dimensions Ø 2.45 in x 3.21 in Ø 62.3 mm x 81.5 mm

Mass, less cables 1.2 lbs 0.55 kg

No Load Speed 7,120 rpm

Max Motor Torque, typ 36.8 in-oz 260 mNm

Min unpowered Holding Torque 38 in-oz 270 mNm

Holding Torque Type Friction Brake

Life (2X Margin) 52,600,000

Electrical


Motor Kt, nominal 5.24 in-oz/A 37.1 mNm/A



Driver type 3-Phase

Redundancy Brake coil only


Environmental

Operating temperature range -94°F to +158°F -70°C to +70°C

Qualified temperature range -67°F to +158°F -55°C to +70°C

Non-Operating temperature range -211°F to +257°F -135°C to +125°C




Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems Rotary Drive Electronics (RDE) is a robust redundant motor controller designed to operate in the extreme environments of space. The RDE provides the interface platform between spacecraft commands and the permanent magnet stepper motor of the Rotary Drive Assembly (RDA).

As a stand-alone unit, the single-channel RDE receives commands and transmits telemetry via a Mil-Std-1553 serial data bus. The I/O through the 1553 bus is controlled by an internal Field Programmable Gate Array (FPGA). Commands are received and processed to determine the appropriate RDA motion sequence. The FPGA controls motion through a collection of control signals and data lines that in turn control output amplifiers. The RDE can also process RDA status information (e.g., rotational position telemetry) and transmit collected information when requested via the 1553 interface.

In the microstep operational mode, the RDE controls individual motor phases with two quadrature sinusoidal signals. The phase and frequency of the sinusoidal drive signals are controlled by a commanded step rate. This ability to drive stepper motors in microstep mode provides the added benefits of control stability and low disturbance torque.

Features

2-phase stepper motor controller, redundant Flight-qualified; heritage design

1553 command Interface EMI/EMC compliant enclosure

Telemetry processing (rotary potentiometer) Radiation-hardened components

Dimensions

Note All dimensions above are in inches.


Space Systems





Applications

Solar Array Drive Assembly (low-disturbance torque)

Heritage Programs

WorldView-1 and –2 Joint Polar Satellite System (JPSS-1)

Suomi National Polar-orbiting Partnership; NPOESS Preparatory Project (NPP)


U.S. SI

Mechanical

Envelope 5.0 in x 9.0 in x 4.0 in 12.7 cm x 22.9 cm x 10.2 cm

Weight ≤ 8.5 lb ≤ 3.9 kg

Electrical

Supply voltage 22-35 Vdc

Power consumption 11.8 W (max.) @ 35 Vdc, single channel

0.1 W (max.), quiescent

Command interface Mil-Std-1553 serial data bus

Microstep range 20 to 26 µsteps per step

Operational modes Position (angle), Track (rate)

Idle (disabled); Stop (no step, enabled)

Interface connectors D-Subminiature per Mil-C-24308

Environment

Temperature (operational) -4 °F to +140 °F -20 °C to +60 °C

Vibration (random) ≤ 12 grms N/A

Vacuum < 1 x 10-5 Torr < 133 x 10-5 Pa

Life > 7.5 years N/A


Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems Simple Stepper Driver (SSD) provides two fully independent motor control channels using an analog design that has many benefits including low-cost.

The SSD is designed to drive two 3-phase bipolar motors and consists of two completely block redundant channels with each channel controlling a single set of stepper motor windings. It is capable of performing cardinal stepping via digital inputs from the command interface connector. Depending on the application, the device can be assembled and qualified to meet EEE-INST-002 Level 1 or Level 2 spaceflight applications.

The SSD receives command signals and power from the host spacecraft and generates signals to independently drive two stepper motors as well as provide eight telemetry pass-throughs for each channel.

The SSD is capable of driving a wide range of stepper motors. Motor winding resistance, motor torque constant, bus voltage, and speed range need evaluation for any application to ensure desired performance is possible.

Features

3-phase bipolar stepper motor operation Independent control of each motor output channel

Primary and Secondary are fully block redundant PWM generation 70-90 kHz motor switching frequency

No FPGA or microprocessor lowers cost/complexity Current limiter (2 configurable current levels)

Linear Power supply (no switching converter) Integrator based current controller

Dimensions



Space Systems





Applications

Antenna pointing Solar array drives

Bi-axis gimbals Actuators


U.S. SI

Mechanical

Envelop dimensions 5.0 in x 3.625 in x 2.5 in 12.7 cm x 9.2 cm x 6.35 cm

Mass < 1.8 lb < .82 kg

Electrical

Input operating voltage 29 Vdc ± 7 Vdc

Power Dissipation (excluding pass thru power) < 7 W

Inrush current ≤ 4.3 A for 2 ms

Power isolation ≥ 1 mΩ power to chassis ground

Motor Current Output < 2 A

Motor Winding Type 3 Phase Bipolar

Operational

Input commands Enable/disable, direction, current setpoint, and step

Step Rate Capability 0 to 2380 Steps per Second

Reverse Voltage Not damaged by reverse voltage

Telemetry Outputs Eight analog pass-throughs available for each axis

Environmental

Operating temperature -40°F to 167°F -40°C to 75°C

Nonoperating temperature -40°F to 212°F -40°C to 100°C

Radiation 100 krad TID (SI)

Vibration 25 g (sine sweep) 35 to 70 Hz


Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems has designed, developed, and delivered an incremental actuator configured around a Size 23 hybrid stepper motor and a 10:1 planetary gearhead, providing output step resolution of 0.18° per motor step. The Size 23 Rotary Actuator was originally developed and qualified for a solar array drive application but is useful for any open-loop stepper motor driven system that needs fine incremental motion but can tolerate a small amount of backlash.

SNC’s Size 23 actuator is composed of a 2-phase, bipolar, 1.8-degree hybrid stepper motor with redundant windings that are insulated from one another to prevent failure propagation. The motor is directly coupled to a 10:1 planetary gear reducer, which features high strength and low backlash. The motor can be provided without the planetary stage and has a detachable shaft so that it can be mated to a different transmission or used as a direct drive motor. The output shaft can be provided with a spur gear, splined interface or other configuration. The redundant motor leads exit through the rear of the motor in two locations and are continuously shielded from the housing to the ends of the cables.

Features

High torque density, 2-phase, 1.8° hybrid stepper motor Removable transmission assembly

Redundant stator windings Replaceable motor shaft extension

10:1 low-backlash, high strength planetary gear set Fully shielded flying lead cabling

Dimensions



Space Systems





Applications

Solar array drives Antenna gimbals

Heritage Programs

Qualified but not yet flown for a SADA application


U.S. SI

Mechanical

Actuator size (OD x L) Ø2.8 in x 4.5 in Ø71.1 mm x 114.3 mm

Actuator mass 2.0 lb 0.9 kg

Motor mass 1.3 lb 0.6 kg

Output Torque, maximum 58.0 in-lb 6.6 Nm

Step size 0.18° with gearhead, 1.8° without gearing

Backlash 0.2° typical, 0.4° max.

Electrical

Motor type 2-phase, bipolar, redundant, 1.8° stepper


Resistance (at ambient temperature) 120 Ω

Driver type 2-phase, bipolar (or 4-phase unipolar with reduced torque)

Qualified Environments

Random vibration 10.5 grms; 180 s / axis

Sine vibration 13.0 g; 2 octaves / min / axis

Pyrotechnic shock 1,865 g; 3 events / axis

Temperature, operating -4 °F to +176 °F -20 °C to +80 °C

Temperature, survival -40 °F to 185 °F -40 °C to +85 °C


Space Systems





T25 Incremental Rotary Actuator (RA)

Design Description

Sierra Nevada Corporation’s (SNC) Space Systems has designed and manufactured the T25 Incremental Rotary Actuator (RA) to meet the demands for a standard, low-cost, space-rated RA. Used for antenna pointing assemblies or to for solar arrays to maintain proper tracking, these T25 RAs meet multiple application requirements with the same design.

The T25 RA features a 24 Vdc, 3-phase, permanent magnet, 1.5-degree stepper motor with redundant windings that are insulated from one another to prevent failure propagation. The motor has been sized with abundant torque margin, based on magnetic modeling and optimization, which ensures that it provides maximum performance per unit weight.

The motor is directly coupled to a 200:1 T-Cup harmonic drive gearbox for maximum stiffness and zero backlash. The high gear ratio provides high internal torque margins throughout the performance range and allows for a significant reduction in the required motor size. Thus, the T25 RA is a significantly lighter actuator with exceptional output capability. Motor position is provided by a fine optical incremental encoder, while position telemetry is sensed by redundant coarse encoders attached to the output. The position accuracy is within a single motor step (.0075 degrees) over the full operating range. Oversized 440C stainless steel ABEC 7 ball bearings support the output shaft for maximum stiffness and life. For more severe bending moment/load applications, an enhanced T25 design with strength-optimized cross-sections is also offered and qualified. SNC fabricates the RA’s structural components from lightweight high stiffness titanium and high-strength aluminum alloys. Careful selection of materials and precision-machined components ensures consistent performance over a broad temperature range. The RA is capable of full 360-degree rotation and adjustable hard stops are available to limit travel to any customer requirement. A center thru hole with an inside diameter (ID) of 0.9 inches comes standard with the T25 RA. The center hole is designed for use with an RF rotary joint, cabling, or other access from spacecraft to mechanism.

Dimensions


T25 Incremental Rotary Actuator Global Precipitation Measurement (GPM) High Gain Antenna System (HGAS)

Space Systems





Features

1.5-deg stepper motor with redundant windings Oversized output bearings for enhanced stiffness

200:1 T-cup harmonic drive unit Full 360-deg output rotation

Telemetry provided by coarse encoders (redundant) Center hole for RF joint or cabling (Ø.9 inches)

Applications

High Gain Antenna System (HGAS) Single-axis actuator

Gimbal Solar Array Drive Assembly (SADA)

Heritage Programs

Solar Dynamics Observatory (SDO) Global Precipitation Measurement (GPM)

Space Communications and Navigation (SCaN), aka, Communications, Navigation, and Networking

re-Configurable Testbed (CoNNeCT)

Lunar Reconnaissance Orbiter (LRO)


U.S. SI

Mechanical

Actuator size (OD x L) Ø5.8 in x 6 in Ø147.3 x 152.4 mm

Weight 8.15 lb 3.70 kg

Through hole (ID) Ø.945 in Ø24.00 mm

Gear reduction 200:1

Torsional stiffness 340,000 in-lb/rad (38,400 Nm/rad), typical

Moment stiffness 1.1e6 in-lb./rad (125 K Nm/rad), typical

Electrical

Motor type 3-phase, redundant windings, 1.5-deg stepper motor


Resistance, room temperature 50 Ω

Power (@ -10 °C) < 16 W

Encoder accuracy ± 0.01°

Encoder power consumption < 1 W

Thermal

Temperature, operating +14 °F to +122 °F -10 °C to +50 °C

Temperature, survival +5 °F to +131 °F -15 °C to +55 °C


Space Systems

Universal Microstepping Control Driver





Design Description

Sierra Nevada Corporation’s (SNC) Space Systems Universal Microstepping Control Driver (UMCD) is a versatile stepper motor driver providing two channels of motor control with selectable microstep resolution and current limit.

The UMCD’s microstepping capability enables smooth motion for open-loop control of a stepper motor driven mechanism. The microstep resolution can be configured independently for each channel to 1, 2, 4, 8, 16, 32, and 64 microsteps per motor detent.

Torque disturbances generated by stepper motor operation can be reduced by 1 to 3 orders of magnitude depending on the motor and actuator characteristics. SNC specializes in the optimization of motors, gearing, and drives for low-torque disturbance applications.

The UMCD is configurable for 2- or 3-phase bipolar stepper motor control. The UMCD provides up to 1.2 amps of peak current on each channel and operates directly from spacecraft bus voltages of 22 Vdc to 36 Vdc. Current regulation maintains constant peak torque over full input voltage range and variations in motor resistance over temperature. The opto-isolated logic level inputs include commands to provide power to the motor and select the direction of rotation. In addition, a step command enables the motor to advance by one step or microstep per input pulse.

Features

Optically coupled command lines for use in noisy environments

Standard STEP, DIRECTION, ENABLE commands optically isolated for each channel

Two channels independently enabled Each channel drives one motor

Dimensions



Space Systems

Universal Microstepping Control Driver




Applications

Antenna pointing Solar array drives

Heritage Programs

GeoEye 1 Samaritan

Geosynchronous Space Situational Awareness Program (GSSAP) 1, 2, 3, and 4

Gladiator


U.S. SI

Mechanical


Mass 2.0 lb 0.9 kg

Electrical

Input operating voltage 28 Vdc ± 6 Vdc

Power Dissipation (excluding pass thru power) ≤1.0 W

Inrush current ≤1.5 A for 7.5 ms

Power isolation ≥ 10 mΩ power to chassis ground

Operational

Input commands Enable, Direction, Step

Logic ‘1’ input level 3.8 V ≤ V in ‘1’ ≤ 5.5 V, 5.1 ma ≤ I in '1' ≤ 18 ma

Logic ‘0’ input level 0 V ≤ V in ‘0’ ≤ 0.7 Vdc, Iin ≤ 50 μa

Step mode Cardinal stepping or microstepping

Resolution 1, 2, 4, 8, 16, 32, or 64 μ-step / step (configurable)

Step rate 10,000 μ-steps / s (max.)

Number of phases 2- or 3-phase (bipolar, configurable)

Direction command sense Logic ‘1’ or Logic ‘0’ (configurable, each channel)

Output current/channel Settable from 200 ma to 850 mA peak, each phase

2-phase mode, 16, 32, and 64 μ-step resolution

Settable from 200 ma to 600 mA peak, each phase

2-phase mode, 1, 2, and 8 μ-step resolution

Settable from 200 ma to 1.2 A (max.) peak, L-2L, 3-phase mode, all resolutions

Environmental

Operating temperature -40 °F to +140 °F -40 °C to +60 °C


Radiation 100 krad TID (SI)

Vibration 25 g (sine sweep) 35 to 70 Hz


Space Systems






Introduction

Sierra Nevada Corporation’s (SNC) Space Systems production and test state-of-the-art facilities have more than 100,000 square feet of manufacturing space that is dedicated to spaceflight subsystem and component assembly and test, small satellite end-to-end production, and fabrication of SNC’s Dream Chaser multi-mission space utility vehicle. SNC’s Production and Test Center in Louisville, Colorado performs a wide spectrum of spacecraft integration and test activities such as environmental, thermal vacuum, vibration, and system-level testing for NASA, commercial, and DOD customers. The SNC Production Center offers its customers advanced test simulators as well as cable and harnessing services. Other in-house services include a precision machine shop for machining activities of tight-tolerance hardware (± 0.0002 inch) from conceptual design to rework of existing designs. SNC’s machining equipment includes multiple precision mills and lathes, CNC mills and lathes, horizontal mills, 3D printing, and laser marking engraving.

Test Simulator Capabilities

SNC’s Large Area Pulsed Solar Simulator (LAPSS) is used to verify solar array performance. The LAPSS, located in a large-scale testing zone of the Production and Test Center, simulates the Sun to obtain accurate electrical performance measurements of solar panels. SNC’s LAPSS is capable of measuring panels that are 3.5 m x 3.5 m square with the AM0 (air mass zero) spectrum at a rate of 10 pulses per minute.

Large Area Pulsed Solar Simulator (LAPSS) (See Catalog Introduction section)

Cable and Harnessing Capabilities

SNC’s in-house Cable Laboratory is supported by NASA-certified and trained technicians with more than 25 years of combined experience. SNC Cable Lab personnel routinely manufacture, repair, and integrate flight and test harnessing and cables for a variety of applications.

Cable and Harnessing

Space Systems

Cable and Harnessing Capability





Design Description

Sierra Nevada Corporation’s (SNC) Space Systems maintains an in-house Production and Test Center Cable and Harnessing Laboratory supported by SNC’s NASA-certified and trained technicians with more than 25 years of combined experience. SNC’s Cable and Harnessing Lab personnel routinely manufacture, repair, and integrate flight and test harnessing and cables for NASA, commercial, and DOD customers for a variety of applications.

SNC recently completed cable and harnessing for NASA’s Cyclone Global Navigation Satellite System (CYGNSS) Deployment Module, which was source inspected and qualified in April of 2016. The team completed all CYGNSS cable and harness activities on time and under budget.

SNC’s Cable and Harnessing Laboratory capabilities meet NASA’s upper-tier flight cable and harnessing electrical connective requirements including NASA-Std-8739.3, Soldered Electrical Connections, or the equivalent standard, IPC-J-Std-001E, Requirements for Soldered Electrical and Electronic Assemblies. SNC’s Cable Lab also meets NASA’s standard for harnessing and wiring, NASA-Std-8739.4.

SNC integration and test production personnel follow stringent guidelines, processes, and procedures to ensure flight-qualification requirements are met. The following electrical tests, including tests to chassis ground (i.e. connector body) and isolated shields, are performed prior to assembly certification. Tests include 1) end-to-end pinout continuity/resistance test; 2) insulation resistance testing per Mil-Std-202, method 302 (250 Vac, 60 second, ≤2.5 ma); and 3) DC resistance testing per Mil-Std-202, method 303 (250 Vdc, 60 sec, ≥1 mohm). An example of our harnessing test activities for the CYGNSS electrical interface is shown below.

Cable and Harnessing for NASA’s CYGNSS Program

Cable and Harnessing Laboratory. Recently completed cable harnessing and testing for the CYGNSS module meeting strict NASA standards.

Space Systems





Features

Fully certified In-house Cable and Harnessing Laboratory Staffed with 25 plus years of experience

Conformance with NASA and Government standards

Applications

Space flight harness assemblies for spacecraft and launch vehicles.

Heritage Programs

NASA Cyclone Global Navigation Satellite System (CYGNSS) Deployment Module

ORBCOMM Generation 2 (OG2)

Space Test Program Satellite (STPSat-5) NASA Commercial Crew Development (CCDev); Commercial Resupply Services (CRS2) programs—Test harnessing and cables for Dream Chaser Engineering Test Article (ETA)

Reference Documents (Process Procedures)

D20234 Kit Verification P5009 Staking Procedure

D20234 Kit Verification P5009 Staking Procedure

P1001 Flight Clean P5013 Torque Procedure

P2004 Identification and Marking of Hardware P5014 Kitting

P3001 Dimensional Inspection P5016 Shrink Tube Installation

P3007 Visual Inspection P5026 Crimping and Installation of Crimp Contacts

P4001 Certify Product (post kit) P8002 Bag & Tag

P4003 Certify Part (pre kit) P10001 Cleanliness

P5008 Preparation of Two-Part Compounds P10002 Electrostatic Discharge (ESD)

ISO-4020 Product Realization ISO-4021 Nonconformances

Note: This data is for information only and subject to change. Contact Sierra Nevada Corporation for design data. “P” and “D” numbers reference internal SNC procedures.

Typical Harness Process and Flow Procedures

Space Systems

Spacecraft Servicing Technologies

This Product is Export Controlled Under Export Administration Regulations (EAR) ©2020 Sierra Nevada Corporation This Product is Export Controlled Under the Export Administration Regulations (EAR) 121



Spacecraft Servicing Technologies

Satellite servicing technologies are truly crosscutting, as they offer a suite of capabilities applicable to such diverse missions as assembling an observatory or habitat in space, catching up with an asteroid, or fixing a spacecraft or ground station on a trip to Mars. They are also game changing, as they allow developing missions a considerably larger trade space to make cost-efficient decisions on redundancy, fault tolerance, and mass allocation.

SNC has developed a number of products and capabilities that directly support spacecraft servicing applications. Catalog data sheets for the Sierra Nevada Corporation’s Spacecraft Servicing Technologies product area include:

Advanced Manipulator Technology for Spacecraft Servicing

Orbital Express Capture System (OECS)

Structural, Power and Data Port (SPDP)

Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) personnel have developed an advanced design approach for robotic manipulators, primarily for satellite servicing tasks. The resulting devices are strong, versatile, reliable, straightforward to analyze, and easy to control.

Key elements of SNC’s design are simplified kinematics, optimal redundancy, high wrist dexterity, active compliance control, simple user interfaces, a compact and rigid tool exchange mechanism, and modularity. We have demonstrated Prototype integrated manipulator modules to Technology Readiness Level (TRL) 5 in thermal vacuum and vibration tests. Suites with multiple full arms have been exercised extensively in 1-g and neutral buoyancy simulations of spacecraft servicing operations.

SNC’s Space Systems expertise in space mechanism design, efficient actuator packaging, auxiliary sensors, and alignment aids support the capability to construct a complete robotic servicing system with unprecedented utility.

Features

Simplified kinematics Optimal redundancy

High-wrist dexterity Active compliance control

Simple user interfaces Compact and rigid tool exchange mechanism

Modularity

Ranger Mk. 2 Manipulators at the University of Maryland demonstrate advanced technology.

Credit: University of Maryland

Two Ranger arms simulating satellite-servicing tasks at the Naval Research Lab. Credit: University of Maryland

Space Systems

Orbital Express Capture System





Design Description

Autonomous docking operations are a critical aspect of unmanned satellite servicing missions. Tender spacecraft must be able to approach the client spacecraft, maneuver into position, and then attach to facilitate the transfer of fuel, power, and replacement parts.

The philosophical approach to the docking system design is linked to the overall servicing mission. The docking system functionality must be compatible with the maneuverability capabilities of both of the spacecraft involved.

The Sierra Nevada Corporation Capture System was flown and operated on the Orbital Express mission. The Capture System performed as intended and has contributed to demonstrating the feasibility of autonomous docking and un-docking of independent spacecraft. The Orbital Express program was intended to develop a cost-effective standard architecture for autonomous servicing. Crucial to this architecture is the effective means by which to capture, provide secure mechanical connection, and make fluid and electrical connections between two spacecraft.

The Capture System consists of an Active side and a Passive side. The Active side contains the grappling arms and drive system; this side would normally be part of the supply spacecraft. The Passive side provides capture features and a sensor to indicate proper engagement of the grappling arms; this side would normally be a part of the client spacecraft.

Features

Simple design with minimized part count Provides interface area for fluid and electrical couplings

Single, motion force for all operations (uses single micro-stepped stepper motor with redundant windings)

Accommodates design scalability

Accommodates a universal interface Physical mating alignment features

Proximity switch provides indication of capture Electrical Control Unit for motor with MIL-STD-1553 serial data interface included as part of the system

Orbital Express Docking Mechanism (image courtesy of the National Air and Space Museum – Smithsonian Institution)

Shown to the left: NEXTSat is 14 m away during a departure. Shown to the right: Progressive side view configurations of the “Berthing” to “Mated” states. Images courtesy of NASA.

https://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&ved=2ahUKEwicv-TEnK3jAhX-Ap0JHfJNDf0QjRx6BAgBEAU&url=https%3A%2F%2Fairandspace.si.edu%2Fcollection-objects%2Forbital-express-capture-mechanism&psig=AOvVaw3EqpxH2yKXRsHyhpGGiN4d&ust=1562946698473378

Space Systems





Dimensions



Active Passive

U.S. SI U.S. SI

Envelope dimensions 33 in H x Ø18 in 838 mm x Ø457 mm 10 in H x Ø18 in 254 mm x Ø457 mm

Mass (including cables) <50 lb <22.7 kg <25 lb <11.3 kg

Axial capture distance 6 in

Angular capture misalignment tolerance

Pitch/Yaw = +/- 5°, Roll = +/- 5°

Lateral misalignment tolerance +/- 2 in

Linear contact velocity tolerance 3 cm/sec

Capture time <10 seconds

Capture and latch time <300 seconds


OE Astro and NEXTSat spacecraft shown mated by OECS during flight. Image courtesy of NASA.

Space Systems






Design Description

Designed as a tool holder for a robotic servicing satellite, the SPDP consists of an Active unit and Passive unit that can be mated and locked together, or unlocked and demated. The Active unit consists of 1) a launch-restraint system, 2) electrical pass-thru cables, 3) a payload locking mechanism, and 4) a stepper gear motor to actuate the mechanism. The Passive unit itself has no moving parts and is integrated structurally and electrically to the payload. The Active unit contains onboard telemetry to indicate a ready-to-lock state, locked vs. unlocked, and excessive locking force fault.

The SPDP is capable of supporting an 8.25 kg1 payload through the launch environment with a first mode frequency above 200 Hz. The SPDP is designed to capture and release the payload repeatedly, up to 400 times on orbit, plus up to 1,600 times in ground testing. The Port also supports the transfer of more than two dozen electrical power and data connections across the locked Active-Passive interface.

Note: The SPDP is export controlled under Export Administration Regulations (EAR). Export to foreign entities may require U.S. government authorization. Approved for Public Release, Distribution Unlimited.

Features

Defined capture envelope Driven by heritage stepper gear motor

Mating and locking telemetry feedback Designed for GEO Radiation and low Electromagnetic Interference (EMI)

Active (spacecraft-side) and Passive (tool-side) components

Physical mating alignment features

Lock fault protection Visual alignment and state indicators

Dimensions

Active Unit Passive Unit


1. 8.25 kg payload with a CG offset of 125.4 mm (4.9 in) from the passive unit to payload-mating interface.

Structural, Power and Data Port

Space Systems





Applications

Deployment mechanisms Satellite docking

Robotics applications Launch restraint

On-orbit upgrade – Modular Payload Adaptor

Heritage Programs (Motor only)

Geosynchronous Space Situational Awareness Program (GSSAP)

Space-Based Infrared System (SBIRS)


Active Passive

U.S. SI U.S. SI

Mechanical

Envelope dimensions 10.3 in x 8.6 in

x 5.5 in

261 mm x 217 mm x 139 mm

1.42 in x Ø4.8 in 36.1 mm x Ø121 mm

Mass (including cables) 13.56 lb 6.15 kg 1.27 lb 0.575 kg

Capture Envelope / Load Capability Available Upon Request

Time to Lock / Unlock 15 seconds Lock / 15 seconds Unlock

Life 1600 cycles in air, 400 cycles in vacuum :: 8 years in GEO

Electrical

Gearmotor type 2-phase, 1.8° stepper + 42.8:1 reduction gearbox

Voltage 29.5 to 33.0 Vdc

Resistance 34.5 Ω

Power, nominal 15 W


Pass-thru harness 29 connections, including 6 Power pairs, 4 digital signal pairs, 3 analog signal pairs

Thermal

Operating temperatures -13 °F to + 140 °F -25 °C to +60 °C -76 °F to +185 °F -60 °C to +85 °C

Nonoperating temperatures -58 °F to +158 °F -50 °C to +70 °C -76 °F to +185 °F -60 °C to +85 °C


Space Systems






Sierra Nevada Corporation’s (SNC) Space Systems has extensive experience in the area of spacecraft thermal control. Our portfolio includes thermal louvers that draw from decades of NASA/JPL heritage and are currently supporting a number of interplanetary spacecraft, and heat switches, which for years reliably controlled the main battery temperature on the Mars Exploration Rovers Spirit and Opportunity. Both technologies are considered passive approaches that require no externally supplied power to operate, allowing valuable spacecraft power to be reserved for other needs.

Catalog data sheets for Sierra Nevada Corporation’s Thermal Control Systems technology area include:

Miniature Satellite Energy-Regulating Radiator (MiSER)

Passive Thermal Control Heat Switch

Passive Thermal Louvers

Thin Plate Heat Switch

Space Systems

Miniature Satellite Energy-Regulating Radiator





Design Description

Sierra Nevada Corporation’s (SNC) Space Systems has developed a Miniature Satellite Energy-Regulating Radiator (MiSER) for small spacecraft thermal control. The design consists of a flat radiator panel integrally mounted on a heat switch. The MiSER is mounted to the exterior of the spacecraft with the integral heat switch coupled to the heat load. The heat switch provides passive thermal control to the internal components of the spacecraft. The design is modular with each switch capable of dissipating 12 W. Single panels can be used to control the temperature of specific components or multiple panels can be used to control the temperature of the entire spacecraft. Custom radiator shapes provide the ability to match unusual geometries.

When the temperature of the spacecraft rises above the set-point temperature, the switch conductance increases, allowing the excess heat to be transferred through the switch to the radiator and out to space. The switch conductance decreases when the temperature of the spacecraft drops below the set-point temperature. This insulates the spacecraft from the colder radiator panel and allows it to stay warm using a low-level of standby power.

Features

Low cost Passive operation

High turndown ratio Precise, narrow control band

Robust construction Low mass

Numerous set points available Linear conductance between open/closed valves

Dimensions



Space Systems

Miniature Satellite Energy-Regulating Radiator




Applications

Dissipate heat from spacecraft components such as electronics

Thermally isolate critical areas of spacecraft from cold space environment

Thermally connect/disconnect a radiator based on thermal control system needs

Switch alone can be used to change conductance of thermal path based on temperature

Switch radiator combination useful for controlling temperature locally for small heat generating components

Heritage Programs

Qualification hardware delivered to customer


U.S. SI

Mechanical

Heat switch dimensions 1.26 in x 1.26 in x. 252 in 32.0 mm x 32.0 mm x 6.4 mm

Radiator dimensions 8.5 in x 8.5 in x .075 in (or to custom requirements)

216 mm x 216 mm x 1.9 mm (or to custom requirements)

Heat switch mass 0.705 oz 20 g

Radiator mass (Aluminum) 4.22 oz 120 g

Life cycles (tested) > 100,000

Operation time Depends on heating rate

Thermal


Available set-point temperatures (typical; others available) 14 °F to 122 °F -10 °C to +50 °C

Conductance (total) Closed: 0.74 BTU/hr-in2-F

Open: 0.0095 BTU/hr-in2-F

Closed: 607 W/m2-C

Open: 7.8 W/m2-C

Turndown ratio 78:1

Maximum Q (Power) 40.1 BTU/hr 12 W


Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Passive Thermal Control Heat Switch is a device for controlling the temperature of electronics and instrumentation on satellites and spacecraft. These devices are part of SNC’s family of tools for spacecraft thermal control. They reduce spacecraft power requirements while providing improved control and better reliability at a lower cost than conventional thermal control schemes.

SNC delivered two flight and one qualification heat switch units to the NASA Jet Propulsion Laboratory for the Mars Exploration Rover (MER) program. The heat switches were designed for use in the Martian atmosphere to control the temperature in the electronics and power enclosure of the Rovers. Given the wide fluctuations in environmental temperature during the Martian day and night cycle, switchable thermal conductance between the electronics enclosure and the body-mounted radiators was required to optimize thermal performance and minimize heater power. The switchable conduction path provided a controlled operating environment for the MER electronics and batteries.

These passive control heat switches are another example of SNC’s ability to design a passive thermal mechanism that operates at a specific temperature. The device includes an autonomously created mechanical action that first senses the temperature, and then provides mechanical motion at a pre-determined set point. This type of device is key in creating a thermally initiated, completely passive (no electrical power or controls) switch.

Features

Low cost Robust construction

High turndown ratio Precise narrow control band

Passive operation Linear conductance between open/closed valves

Numerous set points available Large gap for use in Mars atmosphere

Dimensions


Passive Thermal Control Heat Switch. Shown here are heat switches with dust cover shields.

Space Systems





Applications


Thermally isolate critical areas of spacecraft from cold space environment

Integrate switches into arrays to control larger areas, odd geometries and/or create adjustable radiating areas

Passively change conductance of thermal path based on temperature

Thermally connect and disconnect a radiator based on thermal system needs

Heritage Programs

Mars Exploration Rovers, "Spirit" and "Opportunity”


U.S. SI

Mechanical

Height and thickness 2.0 in (high) x 1.42 in (diameter) 50.8 mm (high) x 36.1 mm (diameter)

Mass 3.87 oz ~110 g

Life cycles (tested) > 350 tested; > 4,000 on MER

Redundancy No

Operation time Depends on heating rate

Thermal


Available set-point temperatures

(typical; others available)

14 °F to 122 °F -10 °C to +50 °C

Conductance (total) Closed: 6.14 BTU/hr-K

Open: 0.14 BTU/hr-K

Closed: 1 W/K

Open: 0.015 W/K

Turndown ratio 67:1

Maximum Q (Power) 20.48 BTU/hr 6 W


Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems Passive Thermal Louver is based on decades of NASA/JPL flight heritage. The louver provides thermal radiation with a pivoting aluminum blade design that is supported within a lightweight frame. The blades are driven with bimetal actuator springs that are thermally linked with the mounting surface.

A standard louver enables radiation from a mounting surface by opening the blades when the mounting surface temperature exceeds a set point. Mounted to a heat source, the louver faces a cold sink (usually space vacuum). The blades operate from fully closed to fully open within approximately 20 °C. The set point, defined as the point where the blades begin to open, can be set between –20 °C to +50 °C.

Effective emissivity of the louver is defined in terms of the effective combined thermal emissivity of the mounting surface and louver. A louver will provide an effective emissivity of 0.14 or less when all blades are closed and have an effective emissivity of 0.74 or greater when all blades are open. These values assume a radiator mounting surface with emissivity of 0.85 in the IR spectrum. The ratio of the two values is called the turndown ratio, which represents the effectiveness of the louver/radiator combination. The high-temperature blade design allows for intermittent direct solar exposure to 0.6 A.U. Options such as reverse operation and custom sizing are available.

Dimensions


Passive Thermal Louvers 20-Blade and 10-Blade Examples

Space Systems





Features

Lightweight, simple design Multiple sizes to fit many applications

High solar irradiance capability Extensive flight heritage

Passive thermal control Fully redundant mechanics

Grounded to prevent electrostatic discharge (ESD) build up Wide range of operational temperature band and set points

Applications

Passive thermal control of spacecraft during interplanetary missions

Heritage Programs

Juno Mission New Horizons Pluto

QuickBird Rosetta

Parker Solar Probe Restricted program

* Nearly 100 flight units built to date.

Blade Variance Specifications

Louver Size Radiating Area Mass

in2 cm2 oz grams

20-Blade (2 rows) 248 1,600 45.6 1,290 max.

14-Blade (2 rows) 220.8 1,425 29.7 940 max.

10-Blade (1 row) 124 800 31.4 890 max.

7-Blade (1 row) 110.4 712 20.5 580 max.



U.S. SI

Mechanical

Qualified random vibration 12.6 grms

Life cycles 20,000 cycles

Thermal

Thermal control band 57 °F to 68 °F 14 °C to 20 °C

Temperature set point range -4 °F to +122 °F -20 °C to +50 °C

Effective emissivity (with radiator emissivity >.85) Closed: 0.14 max.; Open: 0.74 min.


Space Systems






Design Description

Sierra Nevada Corporation’s (SNC) Space Systems Thin Plate Heat Switch devices passively control the temperature of electronics and instrumentation on satellites and spacecraft. These devices are part of SNC’s family of tools for spacecraft thermal control. They can potentially reduce spacecraft power requirements while providing improved control and better reliability at a lower cost than conventional thermal controls.

The devices provide a variable conduction heat path from the warm electronics or instruments to which they are mounted, to a cold panel or cold sink. The temperature of the electronics is controlled by the passive change in thermal conductance of the heat switch. Thermal conductance is adjusted internally and passively based on the temperature of the warm side of the switch. A self-regulating design allows precise, reliable temperature control.

In a typical application, the thin plate is mounted between an instrument or electronics box and a cold sink, such as a panel that radiates to space. When the electronics get too warm, the switch conductance increases, allowing the excess heat to be transferred through the switch to the cold sink. When the electronics get too cold, the switch conductance decreases, insulating the electronics and allowing them to stay warm using their own heat on a low level of standby power.

Two designs are available—the High-Performance Thin Plate Heat Switch (shown top left) and the Diaphragm Thin Plate Heat Switch (shown top right). Both designs have multiple cells and a footprint that is customized to each specific application; they can be used singly, in a plate form in an array, or in a more complex frame style. The High-Performance Thin Plate Switch is lightweight and has excellent thermal performance. The Diaphragm Thin Plate Switch is designed for extreme high reliability. Both designs are rugged and robust. They provide their own structural support in addition to structural mounting for the electronics or instrument.

Features

Low cost Robust construction

High turndown ratio Precise narrow control band

Passive operation Linear conductance between open/closed values

Numerous set points available Self-regulating design

Dimensions

Note: All dimensions above are in inches. Cell sizes are provided in table.

Thin Plate Heat Switch. The High-Performance Thin Plate Heat Switch (at left) and the Diaphragm Thin Plate Heat Switch (at right) provide reliable low-cost thermal control.

Space Systems





Applications


Thermally isolate critical areas of spacecraft from space vacuum

Integrate switches into arrays to control larger areas, odd geometries and/or create adjustable radiating areas

Heritage Programs

Qualification hardware delivered to customer

Product Specifications—High Performance Thin Plate

U.S. SI

Mechanical

Thickness 0.32 in 8.13 mm

Mass (approximate average density) 0.1 lb/in3 2.72 g/cm3

Life cycles (tested) >100,000

Redundancy Yes, multi-cell

Operation time Varies with heating rate

Single cell size 1.00 in x 1.00 in 25.4 mm x 25.4 mm

Thermal


Max thermal conductance ratio 78:1

Available set point temperatures -14 °F to +122 °F -10 °C to +50 °C

Conductance (maximum) Closed: 0.743 BTU/hr-in2-F Open: 0.0095 BTU/hr-in2-F

Closed: 607 W/m2 - °C Open: 7.8 W/m2 - °C

Max Q (power) per cell 41 BTU/hr 12 W


Product Specifications—Diaphragm Thin Plate

U.S. SI

Mechanical

Thickness 0.25 in 6.35 mm

Mass (approximate average density) Approximately 0.1 lb/in3 Approximately 2.72 g/cm3

Life cycles (tested) >1,000

Redundancy Yes, multi-cell

Operation time Varies with heating rate

Single cell size 1.625 in x 1.625 in 41.3 mm x 41.3 mm

Thermal


Max thermal conductance ratio 92:1

Available set point temperatures -14 °F to +122 °F -10 °C to +50 °C

Conductance (maximum) Closed: 0.743 BTU/hr-in2-F Open: 0.0095 BTU/hr-in2-F

Closed: 607 W/m2 - °C Open: 7.8 W/m2 - °C

Max Q (power) per cell 41 BTU/hr 12 W


Space Systems

Acronym List




Acronym List

Acronym / Symbol

Definition

% Percent

~ Approximately

°C Degrees Celsius

°F Degrees Fahrenheit

µ micro sign or ‘Mu’ symbol

(metric prefix: 0.000001, one millionth)

µA microampere (µ-Ampere)

µm micrometer

A Ampere (or Amp)

(An SI unit of electric current)

ABEC Annular Bearing Engineering Committee

(ABEC scale is an industry accepted standard for the tolerances of a ball bearing)

ABS Asia Broadcast Satellite

ac alternating current

ACBM Active Common Berthing Mechanism

ACE Atmospheric Chemistry Experiment

AEHF Advanced Extremely High Frequency

AFRL Air Force Research Laboratory

AIRS Atmospheric Infrared Sounder (AIRS) Earth Shield

AIS Automatic Identification System

AMC Americom Communications Satellite

APM Antenna Pointing Mechanism

AR Anti-reflective

AWG American Wire Gauge

(A standardized wire gauge system used for diameters of round, solid, nonferrous, electrically conducting wire)

BCD Bolt Circle Diameter

BEAM Bigelow Expandable Activity Module

BOL Beginning of Life

B-SAT (1)

Broadcasting Satellite System Corporation (with hyphen) (One of the largest global satellite operators in the world; located in Japan)

BSAT (2)

Broadcasting Satellite System (no hyphen)

(In reference to telecommunication satellites built for the Japanese satellite operator, B-SAT)

BTU British Thermal Unit

c Centi (one-hundredth; metric prefix: 0.01)

C (1) Celsius

C (2) Cup-type transmission (in reference to products C14 SADA, C20 Actuator, and C50 Actuator)

CAD Computer-Aided Design

CAPS Cassini Plasma Spectrometer

Space Systems

Acronym List




Acronym / Symbol

Definition

CBM Common Berthing Mechanism

CBOD Clamp Band Opening Device

CG Center of Gravity

CIC Coverglass Interconnected Cells

cm centimeter

CMG/AR Cerium Doped Borosilicate Anti-Reflective (A custom Anti-reflective solar glass produced by Qioptiq)

CNC Computer Numeric Controlled (CNC machine)

CNOFS Communications/Navigation Outage Forecasting System

CrIS Cross-track Infrared Sounder

CRS Cargo Resupply Service

CSD Cell Shorting Device

CYGNSS Cyclone Global Navigation Satellite System

d deci (metric prefix: 0.1)

da deca (metric prefix: 10)

dc direct current

deg Degree (angle)

DANDE Drag and Atmospheric Neutral Density Explorer

DMAU Deployment Module Avionics Unit

DMSP Defense Meteorological Satellite Program

DOD Department of Defense

DSCOVR Deep Space Climate Observatory

DSX Demonstration and Science Experiment

DTV DirecTV

ECLSS Environmental Control and Life Support System

ECU Electronic Control Unit

EELV Evolved Expendable Launch Vehicle

EH (1) External Heater (in reference to high output paraffin (HOP) actuator products)

EH (2) Enhanced Hybrid (in reference to gimbals/actuators)

EMI/EMC Electromagnetic Interference/Compatibility

eMotor Electronic Motor

EOL End of Life

EOS Earth Observing System

EPS Electrical Power System

ESD Electrostatic Discharge

ESPA EELV Secondary Payload Adaptor

EPIC Earth Polychromatic Imaging Camera

EVA Extra Vehicular Activity

Space Systems

Acronym List




Acronym / Symbol

Definition

F Fahrenheit (temperature)

FASSN Fast-Acting Shockless Separation Nut

FASTSAT Fast, Affordable, Science and Technology Satellite

FCS Flight Control System

FPGA Field Programmable Gate Array

ft foot or feet

ft/s feet per second

g (1) gram

G (1) Gauge

g (2) gravity (acceleration of Earth’s gravity is written as g’s for gravity-force acceleration)

G (2) Gravitational constant

G (3) giga (metric prefix: 1000000000)

GALEX Galaxy Evolution Explorer

GB Gigabyte

GEO Geosynchronous Earth Orbit

GEVS General Environmental Verification Specification

GN&C Guidance, Navigation, and Control

GOES-R Geostationary Operational Environmental Satellite (R-Series)

GPM Global Precipitation Measurement

GPS Global Positioning Satellite

grms gravity root mean square (acceleration)

GSSAP Geosynchronous Space Situational Awareness Program

H Hybrid transmission type

h hecto (metric prefix: 100 or 102)

HDRM Hold Down Release Mechanism

HEO Highly Elliptical Orbit

HGAS High Gain Antenna System

HOP High Output Paraffin (SNC actuator product)

HTV Hypersonic Transfer Vehicle

Hz Hertz

ICO Intermedia Circular Orbit

ID Inside Diameter

IH Internal Heaters

IKONOS Space Imaging Remote Sensing System

Imp Current at maximum power

in inch

inlb/rad Inch pound per radian (rotary stiffness)

Intelsat International Telecommunications Satellite Organization

Space Systems

Acronym List




Acronym / Symbol

Definition

I/O Input/Output

Isc Current under short-circuit Conditions

ISO International Organization for Standardization

ISS International Space Station

JCSAT Japanese Communications Satellite

JPL Jet Propulsion Laboratory

JPSS Joint Polar Satellite System

JWST James Webb Space Telescope

k kilo (one-thousand or 103)

K Monetary symbol for one-thousand (1,000)

kg kilograms

kHz kilohertz

kN kilo Newton

KOMPSAT Korean Multi-Purpose Satellite

krad kilorad

K-truss A deployable boom arranged in a unique K-type configuration that provides a predictable and orderly folding dynamic as from a stowed to a deployed state.

kW kilowatts (1,000 Watts)

kΩ kilo-ohm (1,000 ohms)

lb pound or pounds

lb/in Pounds per inch (lineal stiffness)

lbf Pound force

(A pound-force is equal to the gravitational force exerted on a mass of one pound on Earth’s surface)

lbm Pounds mass

LAPSS Large Area Pulsed Solar Simulator

LEO Low Earth Orbit

LPSS Low-Profile Separation System

LRO Lunar Reconnaissance Orbiter

LSRM Low-Shock Release Mechanism

LV Launch Vehicle

LVDS Low Voltage Differential Signaling

M mega

(Metric prefix: 1,000,000)

m milli

(Metric prefix: 0.001, one-thousandth)

M2M Machine-to-machine

mA milliampere

MASPEX Mass Spectrometer for Planetary Exploration (Europa Mission)

Space Systems

Acronym List




Acronym / Symbol

Definition

MATLAB Matrix Laboratory

(A numerical computing environment and fourth generation programming language, developed by MathWorks)

max. maximum

Mbps Million bits per second

MEO Medium Earth Orbit

MER Mars Exploration Rover

MexSat Mexico’s next-generation mobile satellite system (English translation)

Mil Military

Mil-Std Military Standard

min Metric abbreviation for minute (no periods)

min. minimum

MIP Mars 2001 In-situ Propellant Production Precursor

MiSER Miniature Satellite Energy Regulating Radiator

MLI Multi-Layer Insulation

mm millimeter

mN-m milli-Newton-meter

ms

or msec

millisecond (one-thousandth of a second)

MUOS Mobile User Objective System

MUSES-C Multi-User System for Earth Sensing

n nano

(Metric prefix: 0.000000001)

N Newton

N/A Not Applicable

N·m A newton meter

(A unit of torque, in the SI system; one newton meter of torque is equivalent to one joule per radian.)

N·m /rad Newton meter per radian

NASA National Aeronautics and Space Administration

NBN National Broadband Network

nm nanometer

(An SI unit of length, equal to 10−9 m or a billionth of a meter)

none none

(Metric prefix 1)

NPOESS National Polar-orbiting Environmental Satellite System

NPP NPOESS Preparatory Project

NRE Nonrecurring Engineering

NSI NASA Standard Initiator

NSS New Skies Satellites

Ø Diameter

Space Systems

Acronym List




Acronym / Symbol

Definition

OAP Orbit Average Power

OD/L Outside Diameter x Length

OG2 ORBCOMM Generation 2

OSIRIS-REx Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer

oz ounce

p pico (metric prefix: 0.000000000001)

Pa Pascal (unit), an SI derived unit of pressure

pA picoampere, an SI unit of electric current, symbol, pA

Pb Chemical symbol for the element lead

PbNp An extreme-pressure lubricant additive where lead naphthenate has been used

PCB Printed Circuit Board

PCBM Passive Common Berthing Mechanism

Pmax Maximum Power

PN Part Number

PNA Powered Nut Assembly

P-POD Poly Picosatellite Orbital Deployer

PRT Platinum Resistance Thermometer

QwkSep® Quick Separation (SNC release device product)

RA Rotary Actuator

rad (1) radian (the SI standard unit of angular measurement)

rad (2) A metric unit measuring radiation dose

RBI Propulsion & Environmental Systems

RDA Rotary Drive Assembly

RDE Rotary Drive Electronics

RF Radio Frequency

ROCSAT Republic of China Satellite

(Renamed FORMOSAT, an Earth observation satellite operated by the National Space Organization [NSPO] of the Republic of China [Taiwan])

rpm Revolutions per minute

RTD Resistance Temperature Detector

(A temperature sensor that accurately measures temperature changes)

s second

(The second (symbol: s) (abbreviated s or sec) is the base unit of time in the International System of Units (SI); prefer the symbol s)

SA Solar Array

SADA Solar Array Drive Assembly

SAGE Stratospheric Aerosol and Gas Experiment

SAR Synthetic Aperture Radar

SBIRS Space-Based Infrared System

Space Systems

Acronym List




Acronym / Symbol

Definition

SCaN Space Communications and Navigation (SCaN) —aka, Communications, Navigation, and Networking re-Configurable Testbed (CoNNeCT)

SCISAT Scientific Satellite

SDO Solar Dynamics Observatory

SES Society of European Satellites (English translation)

SGLS Space-Ground Link Subsystem

SHARC Satellite for High Accuracy Radar Calibration

SI International System of Units

SINDA Systems Improved Numerical Differencing Analyzer

SMA Shape memory alloy

(An alloy that remembers its original, cold-forged shape, returning to pre-deformed shape when heated)

SMART-1 Small Missions for Advanced Research in Technology

SMT Surface Mount Technology

SNC Sierra Nevada Corporation

SOHO Solar and Heliospheric Observatory

SP Shut-off Pin Puller

SPDP Structural, Power and Data Port

STEREO Solar Terrestrial Relations Observatory

STPSat-5 Space Test Program Satellite (Series 5)

T tera (metric prefix: 1,000,000,000,000 or 1012; or one trillion)

T25 T-cup type transmission

TacSat Tactical Satellite

TES Thermal Emission Spectrometer

TID Total Ionizing Dose

TIROS Television Infrared Observation Satellite

Torr (metric symbol)

torr (unit’s name)

Unit of Pressure

(A unit of pressure equal to 1⁄760 of an atmosphere–about 133.3 pascals or 1 mm of Hg)

TBC To Be Confirmed

TRL Technology Readiness Level

TTI Thermospheric Temperature Imager

TVC Thrust Vector Control

UMCD Universal Microstepping Control Driver

UNC United Thread Standard (Coarse threads)

UNEF United Thread Standard (Extra Fine threads)

UNF United Thread Standard (Fine threads)

UNS United Thread Standard (UNC - Coarse threads, UNF - Fine threads, UNEF - extra fine threads)

UTS Universal Technical Systems (Integrated Gear Analysis Software)

UVOT Ultraviolet/Optical Telescope

Space Systems

Acronym List




Acronym / Symbol

Definition

V Volts

Vdc Volts Direct Current

VIIRS Visible Infrared Imaging Radiometer Suite

Vinasat Vietnam Satellite (National Satellite Program for Vietnam)

Vmp Voltage at Maximum Power

Voc Voltage Open Circuit

W Watts

XRT X-ray Telescope

XSS eXperimental Small Satellite